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Purpose: Evaluate patient-reported knee function after arthroscopic partial meniscectomy (APM) and meniscus suture repair in two different age cohorts compared with a normal population., Method: Arthroscopic meniscus surgery was performed on 421 patients at Skåne University Hospital from 2010 to 2014, with a mean (SD) follow-up of 4.2 (1.4) years. Patients and controls were divided into two age cohorts; 18-34 years (younger) and 35-54 years (middle-aged) as well as according to surgery performed; either solely meniscus surgery or with concurrent anterior cruciate ligament reconstruction (ACLR). The outcome is measured with the five subscales of the Knee and Osteoarthritis Outcome Score (KOOS)., Results: No significant difference in outcome after all studied types of meniscus surgeries between younger-aged and middle-aged patients.Younger patients with APM or meniscus suture repair, with or without, ACLR score lower than the normal population in all subscales of KOOS (p<0.001), except in Activities of Daily Living (ADL) for meniscus suture patients.Middle-aged patients with APM score lower in all subscales than the normal population (p≤0.009). Those with meniscus suture repair score lower than the normal population only for the subscales Sport/Rec and quality of life (p<0.001).Both younger-aged and middle-aged patients achieve better KOOS values after meniscus suture repair and ACLR than after all other combinations of surgery., Conclusion: Patients with meniscus injuries do not reach the same KOOS score as the normal population, irrespective of age or type of meniscus surgery performed. However, combined with ACLR in younger-aged and middle-aged patients, meniscus suture gives a better subjective outcome than isolated meniscus surgery., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: A higher alpha angle has been proposed to correlate with lower hip range of motion, but the association in people with longstanding hip and groin pain is currently unclear. The aims were to: (1) assess the association between range of motion and alpha angle in patients with longstanding hip and groin pain; (2) examine if a cut-off value in range of motion variables could identify patients with an alpha angle above or below 60°., Methods: Seventy-two participants were consecutively recruited from an orthopaedic department after referral for hip- and groin-related pain. Passive hip range of motion was measured in flexion, internal rotation with 90° hip flexion, internal rotation in neutral hip position, external rotation with 90° hip flexion, and abduction. The alpha angle was calculated from a frog-leg lateral radiograph. Linear regression examined the association between range of motion and alpha angle, and an ROC-curve analysis was performed to identify the sensitivity and specificity of range of motion cut-offs., Results: Lower range of motion in internal rotation in flexion, external rotation, and abduction were associated with higher alpha angle. Internal rotation of 27° or less displayed good sensitivity (81%) and specificity (85%) to detect an alpha angle above 60°, while a cut-off of 41° in external rotation and 27° in abduction showed a sensitivity of 72% and specificity of 50% and 60%, respectively., Conclusion: Less internal rotation in flexion, external rotation, and abduction are associated with a greater alpha angle in a cohort of people with longstanding hip and groin pain. A cut-off of 27° in internal rotation has good sensitivity and specificity to identify people with an alpha angle above or below 60° and have the potential to be used in the clinical setting to identify patients that require further imaging, or that are unlikely to have cam morphology., Level of Evidence: II., (© 2021. The Author(s).)

Objectives: To compare physical impairments between patients with hip-related pain and those with non-hip-related groin pain, and to compare both patient groups with healthy controls., Design: Cross-sectional., Participants: Eighty-one hip and groin pain patients were consecutively included and categorized into having hip-related pain or non-hip-related groin pain. Twenty-eight healthy controls were recruited., Settings: Tertiary care., Main Outcome Measures: All participants performed physical impairment testing including hip ROM, muscle function, and functional tasks. An analysis of covariates was used for analysis between patients groups and controls., Results: Patients with hip-related pain showed reduced hip ROM in internal rotation compared to patients with non-hip-related groin pain and controls (p ≤ 0.026, d -0.65; -0.97). No differences in muscle function or performance in functional tasks were observed between patients with hip-related pain and those with non-hip-related groin pain (p ≥ 0.136, d 0.00; 0.68). Both patient groups had worse muscle function and worse performance in functional tasks compared to controls (p ≤ 0.048, d -0.67; -1.83)., Conclusions: Both patients with and without hip-related pain had worse muscle function and worse performance in functional tasks compared to matched controls but no differences were observed between the patient groups. Only patients with hip-related pain had reduced ROM in internal rotation., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

To comprehend the most detrimental characteristics behind bone fractures, it is key to understand the material and tissue level strain limits and their relation to failure sites. The aim of this study was to investigate the three-dimensional strain distribution and its evolution during loading at the sub-trabecular level in trabecular bone tissue. Human cadaver trabecular bone samples were compressed in situ until failure, while imaging with high-resolution synchrotron radiation X-ray tomography. Digital volume correlation was used to determine the strains inside the trabeculae. Regions without emerging damage were compared to those about to crack. Local strains in close vicinity of developing cracks were higher than previously reported for a whole trabecular structure and similar to those reported for single isolated trabeculae. Early literature on bone fracture strain thresholds at the tissue level seem to underestimate the maximum strain magnitudes in trabecular bone. Furthermore, we found lower strain levels and a reduced ability to capture detailed crack-paths with increased image voxel size. This highlights the dependence between the observed strain levels and the voxel size and that high-resolution is needed to investigate behavior of individual trabeculae. Furthermore, low trabecular thickness appears to be one predictor of developing cracks. In summary, this study investigated the local strains in whole trabecular structure at sub-trabecular resolution in human bone and confirmed the high strain magnitudes reported for single trabeculae under loading and, importantly extends its translation to the whole trabecular structure.

Positron emission tomography (PET) is a form of nuclear imaging, which quantitatively assesses the metabolic activity through the uptake of radioactive tracers. 18 F-fluoride is a positron-emitting isotope with high affinity for bone. Despite its potential as a non-invasive measure of bone metabolism, quantitative 18 F-fluoride PET has only been used sparsely in orthopaedic applications. It has been speculated that 18 F-fluoride PET characterizes cellular activity of bone forming cells in the early stages of the regenerative process and therefore precedes the mineralization detected by conventional computed tomography (CT). Our aim was thus to combine in vivo PET and CT to map the spatiotemporal course of bone regeneration during fracture healing using an open femur fracture model in the rat and characterize regeneration in untreated and pharmacologically treated fractures using both imaging modalities. We hypothesized that PET 18 F-fluoride tracer activity at an earlier time point is predictive of CT measured bone formation at a later time point. On the basis of the RMSE and R 2 metrics of linear regression models it was conceivable for bone volumes to be predicted up to three weeks in advance in a rodent model (RMSE: 14 mm 3 -18 mm 3 , R 2 : 0.79-0.82). Moreover, the data suggested that 18 F-fluoride positron-emitting activity had the potential to separate bone formation from resorption and thus could be of interest across a wide array of orthopaedic applications. Based on this data, we conclude that 18 F-fluoride positron-emitting activity is strongly correlated to bone formation and could potentially predict the volume of bone regenerated at fracture sites. The volume of bone regenerated at a fracture site can be interpreted as a measure of the healing response and 18 F-fluoride should be further investigated as a predictive diagnostic tool to identify if bone fractures will heal successfully or result in delayed healing or non-union. STATEMENT OF SIGNIFICANCE: We aimed to combine in vivo PET and CT imaging to map the spatiotemporal course of bone regeneration during fracture healing using an open femur fracture model in the rat and characterize regeneration in untreated and pharmacologically treated fractures using both imaging modalities. We hypothesized that PET 18 F-fluoride tracer activity at an earlier time point is predictive of CT measured bone formation at a later time point. Our data suggest that 18 F-fluoride positron-emitting activity can separate bone formation from resorption and thus could be of interest across a wide array of orthopaedic applications including as a predictive diagnostic tool to identify if fractures will heal successfully or result in delayed healing or non-union., (Copyright © 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Long-term stability of endosseous implants depends on successful bone formation, ingrowth and adaptation to the implant. Specifically, it will define the mechanical properties of the newly formed bone-implant interface. 3D imaging during mechanical loading tests ( in situ loading) can improve the understanding of the local processes leading to bone damage and failure. In this study, titanium screws were implanted into rat tibiae and were allowed to integrate for 4 weeks with or without the addition of the growth factor Bone Morphogenetic Protein and the bisphosphonate Zoledronic Acid. Samples were subjected to in situ pullout using high-resolution synchrotron x-ray tomography at the Tomcat beamline (SLS, PSI, Switzerland) at 30 keV with 25 ms exposure time, resulting in a total acquisition time of 45 s per scan, with a 3.6 μm isotropic voxel size. Using a custom-made loading device positioned inside the beamline, screws were pulled out with 0.05 mm increment, acquiring multiple scans until rupture of the sample. The in situ loading protocol was adapted to ensure short imaging time, which enabled multiple samples to be tested with short loading steps, while keeping the total testing time low and reducing dose deposition. Higher trabecular bone content was quantified in the surrounding of the screw in the treated groups, which correlated with increased mechanical strength and stiffness. Differences in screw implantation, such as contact between threads and cortex as well as minor tilt of the screw were also correlated to the mechanical parameters. In situ loading enabled the investigation of crack propagation during the pullout, highlighting the mechanical behavior of the interface. Three typical crack types were observed: (1) rupture at the interface of trabecular and cortical bone tissues, close to the screw, (2) large crack inside the cortex connected to the implant, and (3) first failure away from the screw with cracks propagating toward the screw-bone interface. Mechanical properties of in vivo integrated bone-metal screws rely on a combination of multiple parameters that are difficult to identify and separate one from the other.

Objective: In patients with chronic radicular pain, we aimed to evaluate subgroup differences in 1-yr response to transforaminal epidural steroid injection., Design: In this longitudinal cohort study of 100 subjects, 170 transforaminal epidural steroid injections were performed for 1 yr. The sample was stratified by type of disc herniation (protrusion n = 57, extrusion n = 27), by location of disc herniation (central/subarticular n = 60, foraminal n = 24), by grade of nerve root compression (low-grade compression n = 61, high-grade subarticular nerve compression n = 14, high-grade foraminal nerve compression n = 25), and by positive Slump test (n = 67). Treatment response was evaluated by visual analogue scale leg pain and self-reported disability (Oswestry Disability Index). Logistic regression was used to analyze the predictive value of baseline characteristics including the stratified subgroups., Results: High-grade subarticular nerve compression predicted the 1-yr improvement in both visual analogue scale leg pain (P = 0.046) and Oswestry Disability Index (P = 0.027). Low age (P < 0.001), short duration of leg pain (P = 0.015), and central/subarticular disc herniation (P = 0.017) predicted improvement in Oswestry Disability Index., Conclusions: In patients treated with one or several transforaminal epidural steroid injections due to chronic lumbar radicular pain, clinical findings failed to predict the 1-yr treatment response. Low age, short duration of leg pain, central/subarticular disc herniation, and high-grade subarticular nerve compression predicted a favorable 1-yr response to transforaminal epidural steroid injection.

We have explored the potential of cell factory-derived bioactive molecules, isolated from conditioned media of primary goat chondrocytes, for the repair of subchondral cartilage defects. Enzyme-linked immunosorbent assay (ELISA) confirms the presence of transforming growth factor-β1 in an isolated protein fraction (12.56 ± 1.15 ng/mg protein fraction). These bioactive molecules were used alone or with chitosan-agarose-gelatin cryogel scaffolds, with and without chondrocytes, to check whether combined approaches further enhance cartilage repair. To evaluate this, an in vivo study was conducted on New Zealand rabbits in which a subchondral defect (4.5 mm wide × 4.5 mm deep) was surgically created. Starting after the operation, bioactive molecules were injected at the defect site at regular intervals of 14 days. Histopathological analysis showed that rabbits treated with bioactive molecules alone had cartilage regeneration after 4 weeks. However, rabbits treated with bioactive molecules along with scaffolds, with or without cells, showed cartilage formation after 3 weeks; 6 weeks after surgery, the cartilage regenerated in rabbits treated with either bioactive molecules alone or in combinations showed morphological similarities to native cartilage. No systemic cytotoxicity or inflammatory response was induced by any of the treatments. Further, ELISA was done to determine systemic toxicity, which showed no difference in concentration of tumour necrosis factor-α in blood serum, before or after surgery. In conclusion, intra-articular injection with bioactive molecules alone may be used for the repair of subchondral cartilage defects, and bioactive molecules along with chondrocyte-seeded scaffolds further enhance the repair. Copyright © 2015 John Wiley & Sons, Ltd., (Copyright © 2015 John Wiley & Sons, Ltd.)

The macro- and micro-features of bone can be assessed by using imaging methods. However, nano- and molecular features require more detailed characterization, such as use of e.g., vibrational spectroscopy and X-ray scattering. Nano- and molecular features also affect the mechanical competence of bone tissue. The aim of the present study was to reveal the effects of mineralization and its alterations on the mineral crystal scale, by investigating the spatial variation of molecular composition and mineral crystal structure across the cross-section of femur diaphyses in young rats, and healthy and osteoporotic mature rats (N=5). Fourier transform infrared spectroscopy and scanning small- and wide-angle X-ray scattering (SAXS/WAXS) techniques with high spatial resolution were used at identical locations over the whole cross-section. This allowed quantification of point-by-point information about the spatial distribution of mineral crystal volume. All measured parameters (crystal dimensions, degree of orientation and predominant orientation) varied across the cortex. Specifically, the crystal dimensions were lower in the central cortex than in the endosteal and periosteal regions. Mineral crystal orientation followed the cortical circumference in the periosteal and endosteal regions, but was less well-oriented in the central regions. Central cortex is formed rapidly during development through endochondral ossification. Since rats possess no osteonal remodeling, this bone remains (until old age). Significant linear correlations were observed between the dimensional and organizational parameters, e.g., between crystal length and degree of orientation (R(2)=0.83, p<0.001). Application of SAXS/WAXS provides valuable information on bone nanostructure and its constituents, effects of diseases and, prospectively, mechanical competence., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Background/objective: A biphasic ceramic bone substitute consisting of calcium sulfate and hydroxyapatite has been reported to give good clinical outcome regarding bone regeneration and may serve as a carrier for antibiotics in the treatment of bone infections. Often, the overlying muscle is in direct contact with the synthetic graft. The dissolving bone substitute induces inflammation, which may be harmful to the surrounding soft and muscle tissue. The aim of the present study was to evaluate the surrounding soft tissue reaction and the biodegradation of the biphasic bone substitute., Methods: Rods (3 mm × 6 mm) were cast and implanted in the rat abdominal rectus muscle. The rods were either soaked or not soaked in autologous bone marrow before insertion to induce bone formation. Thirty-two rats underwent bilateral operation. After 6 weeks and 12 weeks, the bone substitute material and the surrounding muscle were harvested. The right rod was evaluated by histology to study tissue reaction and the left rod was analysed with micro-computed tomography and scanning electron microscopy to study bone substitute degradation., Results: The muscle tissue around the material was similar at 6 weeks and 12 weeks, with or without prior treatment with bone marrow. The remaining material showed close contact with the muscle, and blood vessels penetrated the material in both groups. Wide bundles of collagen were embedded around the apatite particles, more at the 12-week time point. No bone formation was found, either at 6 weeks or 12 weeks, and scanning electron microscopy showed that the calcium sulfate phase was resorbed after 6 weeks with the calcium phosphate phase remaining intact. Micro-computed tomography showed significantly more hydroxyapatite at 6 weeks than after 12 weeks., Conclusion: Calcium sulfate hydroxyapatite bone substitute can be used as a carrier for antibiotics or other drugs, without adverse reaction due to the fast resorption of the calcium sulfate. No bone formation was seen despite treating the bone substitute with autologous bone marrow.

Areal bone mineral density (aBMD), as measured by dual-energy X-ray absorptiometry (DXA), predicts hip fracture risk only moderately. Simulation of bone mechanics based on DXA imaging of the proximal femur, may help to improve the prediction accuracy. Therefore, we collected three (1-3) image sets, including CT images and DXA images of 34 proximal cadaver femurs (set 1, including 30 males, 4 females), 35 clinical patient CT images of the hip (set 2, including 27 males, 8 females) and both CT and DXA images of clinical patients (set 3, including 12 female patients). All CT images were segmented manually and landmarks were placed on both femurs and pelvises. Two separate statistical appearance models (SAMs) were built using the CT images of the femurs and pelvises in sets 1 and 2, respectively. The 3D shape of the femur was reconstructed from the DXA image by matching the SAMs with the DXA images. The orientation and modes of variation of the SAMs were adjusted to minimize the sum of the absolute differences between the projection of the SAMs and a DXA image. The mesh quality and the location of the SAMs with respect to the manually placed control points on the DXA image were used as additional constraints. Then, finite element (FE) models were built from the reconstructed shapes. Mean point-to-surface distance between the reconstructed shape and CT image was 1.0 mm for cadaver femurs in set 1 (leave-one-out test) and 1.4 mm for clinical subjects in set 3. The reconstructed volumetric BMD showed a mean absolute difference of 140 and 185 mg/cm(3) for set 1 and set 3 respectively. The generation of the SAM and the limitation of using only one 2D image were found to be the most significant sources of errors in the shape reconstruction. The noise in the DXA images had only small effect on the accuracy of the shape reconstruction. DXA-based FE simulation was able to explain 85% of the CT-predicted strength of the femur in stance loading. The present method can be used to accurately reconstruct the 3D shape and internal density of the femur from 2D DXA images. This may help to derive new information from clinical DXA images by producing patient-specific FE models for mechanical simulation of femoral bone mechanics., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Long bone defects can be managed by the induced membrane technique together with autologous bone graft. However, graft harvest is associated with donor site morbidity. This study investigates if a tricalcium phosphate hydroxyapatite scaffold can be used alone or in combination with bone active drugs to improve healing. Sprague Dawley rats (n = 40) were randomized into four groups. (A) scaffold, (B) BMP-7, (C) BMP-7 + scaffold, and (D) BMP-7 + scaffold + systemic bisphosphonate at 2 weeks. Locked femoral nailing was followed by 6 mm segment removal and implantation of an epoxy spacer. At 4 weeks, the spacers were removed and the defects grafted. Eleven weeks later, the bones were explanted for evaluation with radiography, manual assessment, micro-CT, histology, and Fourier Transform Infrared spectroscopy (FTIR). Isolated scaffolds (A) did not heal any defects, whereas the other treatments led to healing in 7/10 (B), 10/10 (C), and 9/10 (D) rats. Group D had greater volume of highly mineralized bone (p < 0.01) and higher bone volume fraction (p < 0.01) compared to all other groups. A synthetic scaffold + BMP-7 combined with a bisphosphonate improved the callus properties in a rat femoral critical size defect, compared to both BMP-7 and scaffold alone or the two combined., (© 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)

Objective: To examine the association between the relaxation time (T1Gd) of delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) and grade of tibiofemoral joint space narrowing (JSN) and osteophytosis 11 years later, in a cohort of meniscectomized patients., Design: Patients (n = 45) aged 35-50 who had undergone an arthroscopic partial medial meniscectomy 1-6 years earlier, due to degenerative meniscal tear, were examined using dGEMRIC. These patients had no cartilage changes defined as deep clefts or visible bone at the time of arthroscopy. Eleven years later (12-16 years after surgery) 34 of these subjects (76%) were evaluated by weight-bearing knee radiography, and tibiofemoral joint changes were graded according to the Osteoarthritis Research Society International Atlas., Results: Lower T1Gd in the medial compartment was associated with higher grade of medial JSN (grade 0, 351 ms; grade 1, 386 ms; grade 2, 342 ms; grade 3, 259 ms [P for trend < 0.001]) and more osteophytosis (score 0, 371 ms; score 1, 389 ms; score 2, 354 ms; score 3, 289 ms; score 4, 265 ms; score 5, 275 ms [P for trend = 0.001]). Lower T1Gd in the lateral compartment was associated with higher grade of lateral JSN (grade 0, 436 ms; grade 1, 346 ms [P for trend = 0.026])., Conclusion: The current study suggests that lower T1Gd measured with dGEMRIC of medial and lateral femoral cartilage is associated with higher grade of JSN 11 years later, and medially, also with more osteophytosis., (Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

The combination of autograft, BMP and bisphosphonate has been shown to produce strong calluses. In this study, without autograft we investigate the effect of bisphosphonate treatment on BMP-induced calluses, both in bending and in rotation. Sprague-Dawley rats (n = 42) underwent femoral osteotomy and BMP-7 treatment. At 2 weeks an injection of saline or bisphosphonate was administered. The animals were sacrificed after 6 weeks. Both femurs were tested in either three-point bending or twisting. All femurs healed. BMP + bisphosphonate-treatment led to larger calluses (p < 0.05) and in three-point bending, higher ultimate force (p < 0.01) and greater stiffness (p < 0.05) than BMP alone. The BMP + bisphosphonate group was nearly 60% stronger than controls, while the BMP group did not reach the strength (p < 0.05) nor stiffness (p < 0.01) of the controls. In the twisting test, similar trends were found but less pronounced. Three-point bending produced transverse callus associated fractures, whereas the twisting test produced spiral fractures, located in the structurally weaker distal femur. BMP + bisphosphonate-treatment produces calluses that are mechanically superior to calluses induced by BMP alone, when tested both in three-point bending and in twisting. For the mechanical evaluation of pharmacologically enhanced calluses with breaking strengths exceeding the native bone, the bending test is recommended., (© 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)

The objective of the Outcome Measures in Rheumatology (OMERACT) Worker Productivity working group is to identify worker productivity outcome measures that meet the requirements of the OMERACT filter. At the OMERACT 11 Workshop, we focused on the at-work limitations/productivity component of worker productivity (i.e., presenteeism) - an area with diverse conceptualization and instrumentation approaches. Various approaches to quantify at-work limitations/productivity (e.g., single-item global and multi-item measures) were examined, and available evidence pertaining to OMERACT truth, discrimination, and feasibility were presented to conference participants. Four candidate global measures of presenteeism were put forth for a plenary vote to determine whether current evidence meets the OMERACT filter requirements. Presenteeism globals from the Work Productivity and Activity Impairment Questionnaire (72% support) and Rheumatoid Arthritis-specific Work Productivity Survey (71% support) were endorsed by conference participants; however, neither the presenteeism global item from the Health and Work Performance Questionnaire nor the Quantity and Quality method achieved the level of support required for endorsement at the present time. The plenary was also asked whether the central item from the Work Ability Index should also be considered as a candidate measure for potential endorsement in the future. Of participants at the plenary, 70% supported this presenteeism global measure. Progress was also made in other areas through discussions at individual breakout sessions. Topics examined include the merits of various multi-item measures of at-work limitations/productivity, methodological issues related to interpretability of outcome scores, and approaches to appraise and classify contextual factors of worker productivity. Feedback gathered from conference participants will inform the future research agenda of the working group.

Background and Purpose: Bone morphogenic proteins (BMPs) can be used in non-unions to replace autograft. BMPs induce osteoblasts and (less well known) also osteoclasts, which can in turn be controlled by a bisphosphonate. In the present study, our aim was to improve the biological effect of autologous bone graft by adding an anabolic BMP, with or without bisphosphonates, in an open-fracture model prone to non-union., Methods: Rat femurs were osteotomized and fixed with an intramedullary K-wire. Autograft was placed at the osteotomy, mixed with either saline or BMP-7. After 2 weeks, the rats had a single injection of saline or of a bisphosphonate (zoledronate). The rats were killed after 6 weeks and the femurs were evaluated by radiography, micro-CT, histology, and 3-point bending test., Results: All fractures healed. The callus volume was doubled in the BMP-treated femurs (p < 0.01) and increased almost 4-fold in the femurs treated with both BMP and systemic zoledronate (p < 0.01) compared to autograft. In mechanical testing, the autograft group reached approximately half the strength of the contralateral, non-osteotomized femur (p < 0.001). By adding BMP to the autograft, the strength was doubled (p < 0.001) and with both BMP and systemic zoledronate, the strength was increased 4-fold (p < 0.001) compared to autograft alone., Interpretation: The combination of BMP and bisphosphonate as an adjunct to autograft is superior to autograft alone or combined with BMP. The combination may prove valuable in the treatment of non-unions.

Fracture dislocations of the PIP joint are challenging to treat. In hemi-hamate arthroplasty, the palmar lip joint surface is reconstructed using an osteochondral graft from the hamate and the immediate stability permits early movement. In the long term, collapse of non-vascularized osteochondral grafts might lead to degenerative arthritis. We examined the radiographic result after a minimum of 4 years with special reference to the development of osteoarthritis and its relation to clinical symptoms in eight patients, mean age 49 (25-66) years. After a mean of 60 (48-69) months, the arc of motion was 67° (45°-95°) at the PIP joint and grip strength was 91% of the uninjured side. The visual analogue score for pain (0-100) was 10 (0-70) mm. Severe arthritis (grade IV) was found in two and mild arthritis (grade II) in another two patients, but only one of these four cases had troublesome pain. The hemi-hamate technique is an attractive alternative to other treatment options, but some cases develop osteoarthritis in the medium term.

Malunion after a distal radius fracture can be treated with an osteotomy of the distal radius. Autologous iliac crest bone graft is often used to fill the gap, but the procedure is associated with donor site morbidity. In this study a novel fast resorbing biphasic bone substitute consisting of a mixture of calcium sulphate and calcium phosphate is used (Cerament BoneSupport AB, Sweden). Fifteen consecutive patients, with a mean age of 52 (27-71) years were included. All had a malunion after a distal radius fracture and underwent an osteotomy. A fragment specific fixation system, TriMed (TriMed, Valencia, CA), consisting of a Buttress Pin and a Radial Pin Plate were used for fixation and a calcium sulphate and calcium phosphate mixture as bone substitute. The patients were followed for 1 year. Grip strength increased from 61 (28-93)% of the contralateral hand to 85 (58-109)%, p < 0.001. DASH scores decreased from 37 (22-61) to 24 (2-49) p = 0.003. Radiographically all osteotomies healed. An increase of ulnar variance was noted during healing from 1.8 mm immediately postoperatively to 2.6 mm at final follow up. Osteotomy can increase grip strength and decease disability after a malunited fracture. In the present series the bone substitute was replaced by bone, but a minor loss of the achieved radiographic correction was noted in some patients during osteotomy healing. A more rigid fixation may improve the radiographic outcome with this kind of bone substitute., ((c) 2009 Wiley Periodicals, Inc.)

Surgically revised deep infected primary knee arthroplasties reported to the Swedish knee arthroplasty register during the years 1986-2000 were studied with respect to microbiology, antimicrobial susceptibility pattern and changes over time. In early, delayed and late infections, coagulase-negative staphylococci (CoNS) were most prevalent (105/299, 35.1%), and twice as common as Staphylococcus aureus (55/299, 18.4%). In haematogenous infections, S. aureus was the dominating pathogen (67/99, 67.7%), followed by streptococci and Gram-negative bacteria. Methicillin resistance was found in 1/84 tested isolates of S. aureus and 62/100 tested isolates of CoNS. During the study period, methicillin resistance among CoNS increased (p=0.002). Gentamicin resistance was found in 1/28 tested isolates of S. aureus and 19/29 tested CoNS isolates. A relative decrease in infections caused by S. aureus was observed, while enterococci increased. In empiric treatment of infected knee arthroplasty the type of infection should direct the choice of antibiotics. Awareness of the fact that most early infections are caused by CoNS can increase the chances of successful treatment with retained implant. Due to the high rate of gentamicin resistance among CoNS in infected knee arthroplasty, other antibiotics should be used in bone cement at revision.

Background: The activity level and subjective knee function after an anterior cruciate ligament (ACL) injury treated without reconstruction have not been well elucidated., Hypothesis: Patients with ACL injury can achieve good knee function and satisfactory long-term activity level when treated by early activity modification combined with rehabilitation., Study Design: Cohort study (prognosis); Level of evidence, 2., Materials and Methods: One hundred patients with an acute total ACL injury were observed for 15 years. All patients initially underwent arthroscopic surgery and a rehabilitation program. They were advised to modify their activity level, especially by avoiding contact sports. Patients with recurrent giving-way episodes and/or secondary meniscal injuries that required fixation (n = 6) were subsequently excluded and underwent reconstruction (n = 22). Sixty-seven patients with unilateral nonreconstructed ACL injury remained at the 15-year follow-up. The Lysholm knee score, Tegner activity level, and a visual analog score for global knee function were recorded at regular intervals. At the final follow-up, patients were further evaluated with the Knee injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee (IKDC) subjective knee evaluation form., Results: Forty patients resumed their preinjury activity level or higher within 3 years. The median activity level 15 years after injury had decreased from 7 to 4 according to Tegner activity scale (P < .001). The mean Lysholm knee score was 96 and 95, 1 and 3 years after injury, respectively, but declined to 86 after 15 years (P < .001). Forty-nine patients had good/excellent results, and 14 had fair (n = 6) or poor function (n = 8) at 15 years. Patients injured in contact sports scored lower in the quality of life sub-scale of KOOS than those injured in noncontact sports (P < .05). Thirteen of the 67 patients (19%) were reoperated with an arthroscopic procedure because of knee symptoms., Conclusion: Early activity modification and neuromuscular rehabilitation resulted in a good knee function and an acceptable activity level in the majority of the nonreconstructed patients. The decline in activity level of patients engaged in contact sports at the time of injury affected their subjective quality of life more than patients involved in noncontact sports.