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Objective To report on a series of patients treated with immediate unrestricted weightbearing with limited protection following single anchor lateral ligament stabilization. Methods Patients with chronic lateral ankle ligament instability who underwent modified Broström-Gould lateral ligament reconstruction with a single double-loaded anchor were identified. Immediate unrestricted full weightbearing in a stirrup brace was allowed the first postoperative day and accelerated physical therapy was initiated from 2 weeks. Subsequent assessment was performed at a minimum of 1-year follow-up. Results Thirteen patients with a mean age at final follow-up of 49 years (range 21-70 years). Average follow-up was 21 months (16 to 26). American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score and visual analogue scale (VAS) score improved significantly (P < .05) from preoperative to postoperative, respectively (57 to 91, 5.7 to 1.5). Average postoperative Foot and Ankle Outcome Score (FAOS) was 82 (range 52-100). Short Form–12 (SF-12) scores averaged 55 and 49 on mental component and physical components, respectively, consistent with US age-matched averages. No measurable differences in range of motion, ligamentous stability, or Star Excursion Balance Test in the anterior, posterolateral, or posteromedial planes compared to the contralateral side (P > .05) were observed. No recurrence was reported. Conclusion Immediate unrestricted weightbearing in a stirrup brace following single anchor lateral ligament reconstruction is a successful protocol for the treatment of chronic lateral ankle instability. Levels of Evidence Therapeutic, Level IV: Case series

Background: Surgeons who lack experience with total ankle arthroplasty (TAA) may remain hesitant to introduce this procedure owing to previously published results of high complication rates during initial cases. The purpose of the present study was to report the development of a TAA program through intermediate outcomes and complications for an initial consecutive series of TAA patients of a single community-based foot and ankle fellowship–trained orthopedic surgeon with little TAA experience using a co-surgeon with similar training and TAA exposure. Methods: The initial 20 patients following third-generation TAA with a single surgeon were reviewed. Clinical outcomes were measured and radiographs were evaluated to determine postoperative implant and ankle position. Complications were also measured including intraoperative, early (Results: With a minimum follow-up of 2 years and average follow-up of 51 months (range 24-70 months), the mean American Orthopaedic Ankle & Foot Society Ankle-Hindfoot score was 87.7 (59-100) and VAS was 1.0 (0-5.5). All patients were improved following TAA. Radiographic evaluation demonstrated no evidence of component malalignment or ankle joint incongruity. There were no intraoperative complications nor any wound complications. Three patients returned to the operating room for placement of medial malleolar screw placement, and 1 had asymptomatic tibial component subsidence. Conclusions: Orthopedic surgeons with a proper background and updated training may be able to perform TAA with good outcomes. A TAA program was developed to define minimum training criteria to perform this procedure in our community. Our complication rate is consistent with those reported in the literature for experienced TAA centers, which contrasts previous literature suggesting increased complication rates and worse outcomes when surgeons perform initial TAAs. Utilization of an orthopedic co-surgeon was felt to be instrumental in the success of the program. Level of Evidence: Level IV, retrospective case series.

Background: The treatment of displaced, intra-articular calcaneus fractures is controversial. The extensile lateral approach has been historically preferred because it provides excellent exposure and visualization for fracture reduction. However, soft tissue complications with this approach can lead to poor outcomes for patients. Recently, there has been an interest in the minimally invasive treatment of calcaneus fractures. The purpose of the present study was to determine the radiographic reduction of displaced, intra-articular calcaneus fractures and the rate of complications using a 2-incision, minimally invasive approach. Methods: A dual-incision, minimally invasive approach with plate and screw fixation was utilized for the treatment of 32 patients with displaced, intra-articular calcaneus fractures. Preoperative and postoperative calcaneal measurements were taken to assess fracture reduction. Additionally, a retrospective chart review was performed to assess for complications. Results: The mean preoperative Bohler’s angle measurement was 12.9 (range, –5 to 36) degrees and the final postoperative Bohler’s angle was 31.7 (range, 16-40) degrees. One patient (3.1%) had postoperative numbness related to the medial incision in the calcaneal branch sensory nerve distribution. Two patients (6.2%) had a wound infection treated with local wound care and oral antibiotics, while 1 patient (3.1%) had a deep infection that required a secondary surgery for irrigation and debridement. Two patients (6.2%) returned to the operating room for removal of symptomatic hardware. Conclusion: Operative fixation of displaced, intra-articular calcaneus fractures treated with a 2-incision, minimally invasive approach resulted in acceptable fracture reduction with a minimal rate of complications. Level of Evidence: Level IV, retrospective case series.

Category: Hindfoot; Ankle; Diabetes Introduction/Purpose: Achieving adequate fixation is a critical component for successful fusion. Internal fixation can be compromised in the setting of poor bone quality due to open trauma, infection, osteoporosis, neuropathic arthropathy resulting in published ankle non-union rates of 38% in high risk patients. These failures may be magnified by weightbearing non-compliance. While the use of multiplanar external fixation (MEF) alone can be utilized - it can often require an extended period of time within the frame (mean 18 weeks, range 9-28 weeks) and complications such as pin site infections. We hypothesized that hybrid fixation, MEF in conjunction with internal fixation, will provide adequate stability elevating the fusion rates in complex fusion cases while allowing early weight bearing and reduces the MEF time and infection rate. Methods: Eleven patients were identified that demonstrate significant risk factors for a successful fusion (infection, charcot, neuropathy, smoking, history of non-union) that were treated with internal fixation augmented with MEF. Patients with an active infection underwent surgical irrigation and debridement, placement of an antibiotic spacer and a course of intravenous antibiotics six weeks prior to placement of internal fixation. In these cases, MEF was placed at the time of surgical irrigation and debridement to allow for stability. In those patient’s without an active fixation, both the internal fixation and MEF were placed at the same time. Internal fixation construct was based on surgeon preference. Patients were allowed to transfer weight bear at the time of surgery and could advance as tolerated after 2 weeks. CT was utilized to assess fusion. Outcomes measured were fusion rate and occurrence of internal fixation infection. Results: The mean age of patients was 55 (range 26-75), eight patients had diabetes, three were current smokers, two were former smokers, two patients had open trauma, one patient had peripheral neuropathy and one patient had a history of a non- union with known non-compliance. Six patients had an active infection and underwent irrigation and debridement, placement of antibiotic spacer and MEF during antibiotic treatment. Seven patients underwent intramedullary nail fixation, three patients underwent plate and screw constructs and one patient underwent screw only fixation. CT demonstrated fusion in all patients (100%). The mean time for external fixation was 72 days (range 41-111). There were no cases of infected internal fixation. Conclusion: The findings of the current study suggest high rates of hind foot fusion with the use of internal fixation augmented with MEF in a complex patient group with identified high non-union risk factors. Using internal fixation, patients time in the frame is much reduced than published studies evaluating MEF alone for fusion fixation. MEF did not result in any cases of infected internal fixation. Patients with hybrid fixation also benefit from early weight bearing. We emphasize the importance of good surgical technique and infection management using this technique.

Introduction Total ankle arthroplasty (TAA) has become a common procedure in the treatment of end-stage ankle arthritis. Most prostheses utilize an anterior ankle approach, which has been shown to have incisional complication rates of up to 28%, including dehiscence and infection. Wounds in this area can be catastrophic to patient outcomes. Preventing incisional wounds would significantly benefit the patient. The purpose of this study was to evaluate the effect of closed incision negative pressure therapy (ciNPT) in reducing incisional dehiscence and surgical site infection (SSI) after TAA. Materials and methods A retrospective chart review that was approved by the Institutional Review Board (IRB) was performed on patients undergoing TAA. Inclusion criteria were patients undergoing TAA with an anterior incision and ciNPT placed immediately in the operating room. Comorbidities associated with increased wound complications were recorded. Identification of any incisional dehiscence, infections, or deviations from normal postoperative recovery attributed to the former was also recorded. Results Twenty-eight patients met the inclusion criteria. The average age of the patients at the time of surgery was 68 years. Comorbidities associated with compromised healing were obesity (45%), current or former smoking (45%), diabetes (3.5%), and rheumatoid arthritis (7%). There were no postoperative wound complications (100% incisional healing). No patient required any wound-care intervention or had an SSI. None of the patients had any delay in the normal postoperative course. Conclusion Avoiding wound complications in TAA patients is critical to the success of the procedure. This retrospective case series demonstrated 100% healing with the utilization of the ciNPT in both normal and high-risk patients with decreased healing potential. Our results showed a substantial decrease in wound complications and SSIs compared to historical reports. We recommend ciNPT for all TAA procedures utilizing an anterior incision to decrease the risk for wound complications and SSIs.

Background:Traumatic tears of the tibialis posterior (TP) tendon following an ankle sprain are rare. The purpose of this study was to report our case series of TP tendon tears following an ankle sprain.Methods:Patients with persistent TP tendon pain after an ankle sprain were retrospectively identified over a 4-year period and reviewed. A comparison of magnetic resonance imaging (MRI) interpretations by a radiologist and surgeon was made. Patients failing conservative management underwent operative repair of the TP tendon tear and concomitant pathology. Failure of the index surgery was defined as TP tendinosis, which was treated with excision and flexor digitorum longus tendon transfer. Outcomes were measured with the Foot Function Index (FFI) and American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot scores.Results:Thirteen patients were found to have a TP tendon tear following an ankle sprain. The incidence for TP tears with sprains presented to our clinic was 1.04%. MRI identified TP tendon pathology in 4 patients by a radiologist review and in 11 patients by a surgeon review. The most common concomitant pathology was a talar osteochondral defect in 13 of 13 patients and ligament instability in 12 of 13 patients (5/13 lateral, 3/13 medial, 4/13 multidirectional instability). Four of 13 patients failed the index surgery. Of the 9 remaining patients, 4 had clinical follow-up at an average of 4.6 years postoperatively. The average FFI subscale scores were the following: pain, 40.4; disability, 28.9; and activity, 23.6. The average AOFAS hindfoot score was 68.8.Conclusion:Despite being rare, a TP tendon tear should be included in the differential diagnosis for persistent medial-sided pain following an ankle sprain. MRI findings can be subtle. Associated pathology was very common and likely confounded the diagnosis and outcomes. Patients should be counseled on the possibility of poor outcomes and long-term pain.Level of Evidence:Level IV, case series.

Background: Total ankle arthroplasty (TAA) has become a successful treatment for end-stage ankle arthritis. Some patients may still have pain or may present with new pain. Suggested sources of medial pain include tibialis posterior tendonitis, impingement, or medial malleolar stress fracture. Etiology and treatment remain unclear. The objective of our study was to evaluate patients with delayed-onset medial malleolar pain following TAA who underwent treatment with percutaneous medial malleolar screw placement and propose an etiology. Materials and Methods: Patients who had undergone TAA at our institution were reviewed and those with medial malleolar pain were identified. Clinical and radiographic examinations were performed pre- and postoperatively. Radiographs were compared with those from a cohort of controls without a history of medial pain. All affected patients failed conservative therapy and were treated with percutaneous placement of medial malleolar screws positioned from the malleolar tip and extending proximally beyond the tibial component. Postoperatively, patients were placed in an ace wrap and allowed to be weightbearing to tolerance, except for 1 patient initially restricted to partial weightbearing. Visual analog scale (VAS) scores were recorded. Seventy-four (74) patients underwent TAA by the corresponding author. All (100%) were female with an average age of 66 (range, 57-73) years. Average follow-up since screw placement was 21.4 (range, 10-41) months. Results: Six (8.1%) underwent placement of 2 percutaneous medial malleolar screws. Patients presented with pain an average of 12 (range, 4-24) months postoperatively and underwent screw placement an average of 2.8 (range, 1-6) months after presentation. At the time of TAA, none had a coronal plane deformity and none underwent a deltoid ligament release as part of balancing. All (100%) patients had pain and swelling directly over the medial malleolus prior to screw placement. Postoperatively, 1 (17%) had mild pain clinically at this site and 2 (33%) had occasional pain medially with activity. Average VAS scores improved from 5.7 (range, 4-6) preoperatively to 1.3 (range, 0-3) postoperatively ( P < .05). Three (50%) patients had a bone density test and all were normal. Prior to screw placement, radiographs demonstrated no signs of stress fracture or misalignment. Average minimum width of the medial malleolus at the level of the tibial component was 10.2 mm (range, 9.2-11.0), which was significantly less ( P < .05) than the control group of 19 patients whose distance measured 12.2 mm (range, 8.5-14.8). Discussion: Patients who present with new-onset medial malleolar pain with normal radiographs following TAA may have medial malleolar insufficiency fracture. These patients can be treated successfully with minimal morbidity by placement of percutaneous medial malleolar screws. Etiology may be related to deltoid traction, subacute stress fracture, and/or impingement of the talus component on the medial malleolus. Medial malleolar pain may be misdiagnosed as tibialis posterior tendonitis, impingement, or implant failure. This diagnosis should be considered in patients who have pain at the medial malleolus, particularly if they are female or have medial malleolus thickness less than 11 mm at the level of the tibial implant. Placement of prophylactic medial malleolar screws may be considered at the time of TAA when these conditions exist. Level of Evidence: Level IV, case series.

Objective There remains no consensus on a postoperative protocol following arthroscopic treatment of osteochondral lesions of the talus (OLTs) and most studies report a period of immobilization and nonweightbearing. Outcomes are believed to decrease with larger size. The purpose of our study was to evaluate patients who underwent arthroscopic treatment of large (≥150 mm2) OLTs with immediate unrestricted weightbearing and mobilization postoperatively. Design Patients who underwent arthroscopic bone marrow stimulation for osteochondral defects were identified. Exclusion criteria included lesions less than 150 mm2, additional procedures other than ligament reconstruction, incongruent ankle joint, arthritis, and tibial plafond lesions. Postoperatively, all patients were placed into a soft dressing and were allowed immediate weightbearing as tolerated. Patients were considered failures if their AOFAS (American Orthopaedic Foot and Ankle Society) score was less than 80 or if they underwent osteochondral transplant. Results Thirteen patients were available for follow-up. Two patients underwent osteochondral transplant and were considered failures. Of the remaining 11, the average follow-up time after surgery was 33 months (range, 7-59 months). Average age was 37 years (range, 15-56 years), and lesion size averaged 239 mm2 (range, 150-400 mm2). Average postoperative scores included foot function index 50 (range, 23-136), visual analog scale 3 (range, 0-8), and AOFAS hindfoot 82 (range, 40-100). The group’s overall success rate was 54% (7/13). Conclusion The results of our study are higher than those previously published studies on large lesions with a more restricted postoperative rehabilitation, suggesting that unrestricted weightbearing and range of motion does not diminish patient outcomes. Level of Evidence: IV, Case series.

Background: Normal biomechanics of the ankle joint includes sagittal as well as axial rotation. Current understanding of mobile-bearing motion at the tibial-polyethylene interface in total ankle arthroplasty (TAA) is limited to anterior-posterior (AP) motion of the polyethylene component. The purpose of our study was to define the motion of the polyethylene component in relation to the tibial component in a mobile-bearing TAA in both the sagittal and axial planes in postoperative patients. Methods: Patients who were a minimum of 12 months postoperative from a third-generation mobile-bearing TAA were identified. AP images were saved at maximum internal and external rotation, and the lateral images were saved in maximum plantarflexion and dorsiflexion. Sagittal range of motion and AP translation of the polyethylene component were measured from the lateral images. Axial rotation was determined by measuring the relative position of the 2 wires within the polyethylene component on AP internal and external rotation imaging. This relationship was compared to a table developed from fluoroscopic images taken at standardized degrees of axial rotation of a nonimplanted polyethylene with the associated length relationship of the 2 imbedded wires. Sixteen patients were included in this investigation, 9 (56%) were male and average age was 68 (range, 49-80) years. Time from surgery averaged 25 (range, 12-38) months. Results: Total sagittal range of motion averaged 23±9 (range, 9-33) degrees. Axial motion for total internal and external rotation of the polyethylene component on the tibial component averaged 6±5 (range, 0-18) degrees. AP translation of the polyethylene component relative to the tibial component averaged 1±1 (range, 0-3) mm. There was no relationship between axial rotation or AP translation of the polyethylene component and ankle joint range of motion ( P > .05). Conclusion: To our knowledge, this is the first investigation to measure axial and sagittal motion of the polyethylene component at the tibial implant interface in patients following a mobile-bearing TAA. Based on outcome scores and range-of-motion measurements, we believe the patients in this study are a representative cross section of subjects compared to other TAA research results. The results from this investigation indicate the potential for a mobile-bearing TAA to fall within the parameters of normal polyaxial ankle motion. The multiplanar articulation in a mobile-bearing TAA may reduce excessively high peak pressures during the complex dynamic tibial and talar motion, which may have a positive influence on gait pattern, polyethylene wear, and implant longevity. Level of Evidence: Level IV, case series.

Category: Ankle Arthritis Introduction/Purpose: Most current total ankle arthroplasty (TAA) designs attempt minimal bone resection and depend on bone ingrowth for long term survival. The arthritic process may cause subchondral bone cysts (SBCs), which could influence the available bone stock of the already limited distal tibia and talus. The prevalence or pattern of SBC formation in ankle arthritis has not been described. Furthermore, the ability of standard radiographs identifying and quantifying SBC formation is unknown. The purpose of our study is to define the prevalence and patterns of periarticular SBCs in the arthritic ankle and determine the efficacy of radiographs to identify SBCs. We hypothesized that the prevalence of SBCs is greater than determined from radiographs and that SBCs often extend beyond standard cuts for some TAA implants. Methods: We identified patients who presented with end-stage ankle arthritis and had pre-operative weight bearing x-rays and CT or MRI. Demographic data was obtained for each patient. Radiographs were reviewed to determine coronal plane deformity (varus/valgus), as well as the qualitative and quantitative presence of SBCs. The tibia and talus were divided into 6 zones: 1) antero-medial, 2) antero-lateral, 3) centro-medial, 4) centro-lateral, 5) postero-medial, and 6) postero-lateral. The same zones were used when evaluating CT or MRI. SBCs were measured to determine volume. The evaluation of all x-rays and CT/MRI’s was performed independently by three foot and ankle trained orthopaedic surgeons. We determined SBCs that extended >5 mm from the subchondral bone to be significant. We defined diffuse SBCs to be present in three or more zones in either the tibia or talus. Intra and inter-observer reliability was determined. Results: Ninety-five patients were included in our study. The average age was 69.3 years and 69% were male. Definitive treatment included 69 (73%) TAA and 26 (27%) ankle fusions. Neutral alignment occurred in 12%, congruent varus 15% and valgus 0%, and incongruent varus 54% and valgus 19%. Radiographs identified SBCs in 46% of patients and CT/MRI identified SBCs in 92% (p < 0.05). Cysts were present in the distal tibia 26% anterolateral, 17% anteromedial, 17% centrolateral, 17% posterolateral, 15% centromedial, and 9% posteromedial. Cysts were present in the talus 26% centromedial, 19% centrolateral, 19% posterolateral, 14% anterolateral, 12% anteromedial, and 10% posteromedial. 38% of the patients had diffuse SBCs. 52% of the cysts extended beyond 5 mm on either the distal tibia or talar dome. Conclusion: Our study suggests that SBCs are common in end stage ankle arthritis and may be diffuse and extend beyond standard cuts for TAA. Poor residual bone stock could compromise implant longevity and may explain early failures. Radiographs and coronal plane deformity are poor predictors for identifying extent, size, and location of SBCs. The authors recommend CT scans for all patients considered for TAA for preoperative planning for bone grafting, altering bone cut height, implant selection, or determining if the bone stock is suitable for TAA. Further study is needed to determine adequate bone stock for TAA.

There is a paucity of objective information in the literature about first metatarsophalangeal (MTP) hemiarthroplasty. The authors postulate that it is a reasonable treatment option for severe hallux rigidus in selected patients. Twenty-two elective first MTP hemiarthroplasties were performed on 20 patients that met the inclusion criteria. Pre- and postoperative evaluations were done using the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score, visual analogue scale (VAS) pain score, range of motion (ROM) measurements, and radiographs. Average ROM and dorsiflexion improved by 15° and 8°, respectively. VAS pain scores improved from 5 to 2.5 after six weeks. Painless ambulation occurred after six weeks, with maximum improvement by six months. After 24 months, two patients had pain at the surgical site interfering with function, leading to an unsatisfactory result that required conversion to arthrodesis. First MTP hemiarthroplasty for severe hallux rigidus can be considered an alternative to fusion in properly selected patients who wish to maintain a functional range of motion.

Category: Diabetes Introduction/Purpose: Management of patients with lower extremity wounds is complex and generally attributed to diabetes, neuropathy, and/or peripheral vascular disease (PVD). Often, these patients have poor control of their disease and limited resources. Hospitalizations related to lower extremity wounds are expensive with relatively high length of stay. Much of this time is spent organizing outpatient interventions. The purpose of this study is to evaluate the efficacy of outpatient surgical management of patients with lower extremity wounds that could lead to hospitalization. We hypothesize that through a multispecialty wound clinic, utilizing wound care specialists, orthotist/prosthetist, infectious disease specialist, and orthopaedic surgeons, at-risk patients could be identified for non-healing wounds through successful outpatient surgical management with preoperative insurance approval of postoperative wound care, offloading devices and antibiotic treatment. Methods: Patients seen through our outpatient multispecialty wound clinic were evaluated and those who underwent an outpatient surgical procedure over a 12-month period were identified. Additional inclusion criteria included failure of non-surgical management and 90-day minimum follow-up. Exclusion criteria included any patient who was septic, medically unstable, or unable to comply with the postoperative plan. Preoperative parameters regarding disease severity (HbA1c), infection severity (WBC, ESR, CRP), and wound healing potential (albumin, total protein) were identified. In addition, preoperative determination of wound severity was measured using Wagner’s Score. Outcomes included hospitalizations related to their wound within 90 days, requirements for additional surgical procedures, and time to resolve their wound postoperatively. Results: Nineteen patients met the inclusion criteria. Average age was 58.6 years and eleven were male. Ten had diabetes, thirteen had neuropathy, and five had PVD. Average preoperative HbA1c was 7.9, and average WBC, CRP, ESR, albumin, and total protein was 8.1, 1.1, 29.6, 3.7, and 7.0, respectively. All patients had preoperative conservative intervention. Eight patients were preapproved for outpatient IV antibiotics and four for wound vac therapy. Table 1 outlines the procedures performed. Patients presented an average of 7.3 weeks following their outpatient procedure until resolution of their wound. One patient was re-admitted to the hospital within 90 days for a problem related to their initial wound. Conclusion: Our study demonstrates that outpatient surgical management of medically stable patients with lower extremity diabetic, neuropathic, and/or PVD wounds resulted in wound resolution and eliminating hospitalization. This is accomplished with the preoperative organization through a multispecialty wound care clinic for patient’s postoperative needs, eliminating the time spent in the hospital during admissions waiting for OR availability, insurance approval and organization of outpatient wound care and antibiotics. This traditional process results in high medical costs without active intervention. Outpatient management can save valuable hospital resources as well as a substantial cost savings by eliminating days spent in the hospital.

Fat emboli syndrome is a well-recognized complication of displaced long bone fractures, often times requiring internal fixation. Treatment is generally supportive and is most successful with early diagnosis. This article describes a case of fat emboli syndrome resulting from a nondisplaced tibia fracture treated with long leg casting. This case demonstrates that fat emboli should be considered as a potential complication of any long bone fracture and should be part of the differential diagnosis for any patient unconscious or in respiratory distress that has sustained a recent long bone fracture.

Level of Evidence: V, Expert Opinion

It is controversial as to whether debris from hydroxyapatite (HA)-coated implants jeopardizes the long-term success of total joint replacements. It has been hypothesized that liberated HA particles are engulfed by macrophages and through normal cellular digestion prevent osteolysis and third-body wear. HA particulates, however, have been observed at the interface and on polyethylene articulating surfaces. There is limited data demonstrating the ability of HA to dissolve at the acidity levels associated with macrophage organelle digestion. The objective of this study was to determine if particulate HA could dissolve at the pH levels found in macrophage organelles. Characterized HA particles were placed into buffered solutions corresponding to phagosomal organelle pH levels: cytoplasmic (pH 7), phagosomal (pH 6), and lysosomal (pH 5). Flasks were under continuous agitation in a shaker chamber at 37°C. Calcium and phosphate ions were measured beyond the maximum life span of an activated macrophage. The data showed that calcium ions rose within the first 24 h and then remained constant throughout the experiment for all pH groups. Phosphate ion concentration showed a similar pattern at the lysosomal pH but remained undetected at the other organelle pH levels. The saturation point was highest at the lysosomal pH level and lowest at the cytoplasmic pH level. The results of this experiment leave the potential for HA particles to dissolve following macrophage digestion. However, caution must be exercised when interpreting the macrophage organelle digestion hypothesis; the size of the HA particle, the length of time required to completely dissolve the particle, and potential cellular toxicity all are factors that have yet to be determined before this hypothesis can be validated. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 40, 104–114, 1998.

Background: Osteochondral injury of the talus can be challenging to treat because the damaged articular cartilage has a poor intrinsic reparative capability. Autologous Chondrocyte Implantation has become an effective means for treating persistent cartilage lesions that fail to respond to routine ankle arthroscopy. The purpose of this study was to assess the results of Matrix-induced autologous chondrocyte implantation (MACI) for the treatment of osteochondral defects of the talar dome using a technique which does not require an osteotomy of the tibia or fibula. Materials and Methods: A prospective investigation of MACI was performed on ten patients with full-thickness lesions of the talus. The patients had a documented talus lesion on MRI, failure of conservative treatment and arthroscopic debridement/curettage, persistent ankle pain and swelling, the absence of tibiotalar arthritis and a stable ankle. Five males and five females, with an average of 1.7 previous procedures prior to Matrix-induced autologous implantation, were included in this study. All patients were available for followup at 1 and 2 years. Lesions were graded during the harvesting procedure using the Cheng-Ferkel grading system, the Outerbridge classification, and the International Cartilage Repair Society system. Clinical and functional evaluation was done preoperatively, and at 1 and 2 years postoperatively using the AOFAS hindfoot evaluation and the SF-36 Health Survey. Results: Preoperative AOFAS hindfoot scores were 61.2 (range, 42 to 76) which improved 1 year postoperatively to 74.7 (range, 46 to 87) ( p < 0.05) and 2 years postoperatively to 73.3 (range, 42 to 90) ( p = 0.151). At both 1 and 2 years postoperatively, the results of the SF36 evaluation demonstrated a significant improvement in the Physical Functioning ( p = 0.002) and Bodily Pain ( p < 0.001) components. Subjectively, all ten patients believed this procedure helped them. Conclusion: The results of this study suggest that MACI may be an effective way to treat full-thickness lesions of the talus using harvested chondrocytes from the talus without malleolar osteotomy. We recommend it for patients who do not respond to initial curettage and microfracture. Level of Evidence: IV, Retrospective Case Series

Questions persist concerning the incidence of total hip arthroplasties (THAs) attributable to secondary osteoarthrosis and the impact of corrective pediatric hip surgeries and retained internal fixation on subsequent THAs. Hip reconstruction fellowship directors (N = 72) were mailed a survey of multiple-choice questions about pediatric hip disorders (PHDs) in their THA populations, the influence of hip osteotomies on subsequent THAs, and the recommendation to routinely remove pediatric hip internal fixation. Forty-five surgeons (62.5%) responded. The majority reported that a small proportion of hip arthrosis in their practice was attributable to PHDs (10-30 cases per 100-200 annual cases). Fifty-seven percent indicated that hip surgery performed during skeletal immaturity made THA more difficult. Twenty-eight surgeons (62% of respondents) said that they remove implants from fewer than 10% of cases with previous pediatric surgery. Sixty-eight percent felt that removal of pediatric hip implants, particularly those in the proximal femur (83% of respondents), should be routine. Survey results showed that the majority of experts in adult hip reconstruction (a) do not identify PHDs as a significant factor in most of their patients with end-stage hip arthrosis and (b) believe in routine removal of pediatric hip implants, particularly those in the proximal femur. The impact of performing corrective hip surgery during skeletal immaturity--whether such surgery increases the difficulty of or diminishes the effectiveness of subsequent THA--remains controversial.