Return to sports after arthroscopic debridement and bone marrow stimulation of osteochondral talar defects: a 5- to 24-year follow-up study.

PURPOSE: Osteochondral defects (OCD) often have a severe impact on the quality of life due to deep ankle pain during and after weight bearing, which prevents young patients from leading an active life. Arthroscopic debridement and bone marrow stimulation are currently the gold standard treatment. The purpose of this study was to evaluate the number of patients that resume and maintain sports to their pre-injury activity level after arthroscopic debridement and bone marrow stimulation. METHODS: This retrospective study evaluated patients treated with arthroscopic debridement and bone marrow stimulation between 1989 and 2008. All patients who were participating in sports before injury were included. The Ankle Activity Scale (AAS) was used to determine activity levels during specific time points (before injury, before operation, after operation and at the time of final follow-up). RESULTS: Ninety-three patients were included. Fifty-seven (76%) patients continued participating in sports at final follow-up. The median AAS before injury of 8 (range 3-10) significantly decreased to 4 (range 2-10) at final follow-up. CONCLUSION: It is shown that 76% of the patients were able to return to sports at long-term follow-up after arthroscopic debridement and bone marrow stimulation of talar OCDs. The activity level decreased at long-term follow-up and never reached the level of that before injury. The data of our study can be of importance to inform future patients on expectations after debridement and bone marrow stimulation of a talar OCD. LEVEL OF EVIDENCE: Retrospective case series, Level IV.

Computed tomography analysis of osteochondral defects of the talus after arthroscopic debridement and microfracture.

PURPOSE: The primary surgical treatment of osteochondral defects (OCD) of the talus is arthroscopic debridement and microfracture. Healing of the subchondral bone is important because it affects cartilage repair and thus plays a role in pathogenesis of osteoarthritis. The purpose of this study was to evaluate the dimensional changes and bony healing of talar OCDs after arthroscopic debridement and microfracture. METHODS: Fifty-eight patients with a talar OCD were treated with arthroscopic debridement and microfracture. Computed tomography (CT) scans were obtained at baseline, 2 weeks postoperatively, and 1 year postoperatively. Three-dimensional changes and bony healing were analysed on CT scans. Additionally, clinical outcome was measured with the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and numeric rating scales (NRS) for pain. RESULTS: Average OCD size increased significantly (p < 0.001) in all directions from 8.6 (SD 3.6) × 6.3 (SD 2.6) × 4.8 (SD 2.3) mm (anterior-posterior × medial-lateral × depth) preoperatively to 11.3 (SD 3.4) × 7.9 (SD 2.8) × 5.8 (SD 2.3) mm 2 weeks postoperatively. At 1-year follow-up, average defect size was 8.3 (SD 4.2) × 5.7 (SD 3.0) × 3.6 (SD 2.4) mm. Only average defect depth decreased significantly (p < 0.001) from preoperative to 1 year postoperative. Fourteen of the 58 OCDs were well healed. No significant differences in the AOFAS and NRS-pain were found between the well and poorly healed OCDs. CONCLUSION: Arthroscopic debridement and microfracture of a talar OCD leads to an increased defect size on the direct postoperative CT scan but restores at 1-year follow-up. Only fourteen of the 58 OCDs were filled up completely, but no differences were found between the clinical outcomes and defect healing at 1-year follow-up. LEVEL OF EVIDENCE: IV.

Evaluation of the Dutch version of the Foot and Ankle Outcome Score (FAOS): Responsiveness and Minimally Important Change.

PURPOSE: The aim of this study was to evaluate the responsiveness of the Foot and Ankle Outcome Score (FAOS) and provide data on the Minimally Important Change (MIC) in patients 1 year after hindfoot and ankle surgery. METHODS: Prospective pre-operative and 1 year post-operative FAOS scores were collected from 145 patients. A patient's global assessment and a longitudinal derived Function Change Score were used as external anchors. To assess responsiveness, effect sizes (ES) and Standardized Response Means (SRM) were calculated and hypotheses on their magnitudes were formulated. Additional ROC curve analysis was performed, and the Area Under the Curve (AUC) was calculated as a measure of responsiveness. MIC values were estimated using two different methods: (1) the mean change method and (2) the optimal cut-off point of the ROC curve. RESULTS: Responsiveness was supported by confirmation of 84% of the hypothesized ES and SRM and almost all AUCs exceeding 0.70. MIC values ranged from 7 (symptoms) to 38 (sport) points. They varied between calculation methods and were negatively associated with baseline values. A considerable amount of MIC values did not exceed the smallest detectable change limit, indicating that the FAOS is more suitable at group level than for longitudinally following individual patients. CONCLUSIONS: The FAOS demonstrated good responsiveness in patients 1 year after hindfoot and ankle surgery. Due to their wide variation, MIC estimates derived in this study should be interpreted with caution. However, these estimates can be of value to facilitate sample size calculation in future studies. LEVEL OF EVIDENCE: Diagnostic study, Level I.

Treatment of osteochondral defects of the talus with a metal resurfacing inlay implant after failed previous surgery: a prospective study.

We have evaluated the clinical effectiveness of a metal resurfacing inlay implant for osteochondral defects of the medial talar dome after failed previous surgical treatment. We prospectively studied 20 consecutive patients with a mean age of 38 years (20 to 60), for a mean of three years (2 to 5) post-surgery. There was statistically significant reduction of pain in each of four situations (i.e., rest, walking, stair climbing and running; p ≤ 0.01). The median American Orthopaedic Foot and Ankle Society ankle-hindfoot score improved from 62 (interquartile range (IQR) 46 to 72) pre-operatively to 87 (IQR 75 to 95) at final follow-up (p < 0.001). The Foot and Ankle Outcome Score improved on all subscales (p ≤ 0.03). The mean Short-Form 36 physical component scale improved from 36 (23 to 50) pre-operatively to 45 (29 to 55) at final follow-up (p = 0.001); the mental component scale did not change significantly. On radiographs, progressive degenerative changes of the opposing tibial plafond were observed in two patients. One patient required additional surgery for the osteochondral defect. This study shows that a metal implant is a promising treatment for osteochondral defects of the medial talar dome after failed previous surgery.

Morphological analysis of subchondral talar cysts on microCT.

PURPOSE: Osteochondral talar defects often present in conjunction with subchondral bone cysts. The exact aetiology of these cysts is unknown. Recently was shown in a computational bone model that pressurized fluid and osteocyte death could lead to cyst growth, through mechanoregulated bone adaptation. However, a difference in cyst morphology was present between the mechanisms. The purpose of this study was to evaluate and compare the cyst morphology of human cadaveric tali by using microCT with the morphological simulation results previously reported. MATERIALS AND METHODS: Sixty-six fresh-frozen human cadaveric tali were screened in a regular CT for subchondral bone cysts, radiologically defined as unexpected rounded radiolucent area. Subsequently, the tali with a cyst were scanned in a microCT. The shape of the cysts, the presence of an opening through the subchondral bone plate, and the bone volume fraction around and next to the cyst were analysed. RESULTS: In total, six tali were found to have a single cyst. Four cysts had an irregular shape, and two cysts were rounded. A clear opening from the cyst through the subchondral bone plate was found (diameter 0.5-1.7 mm) in four cysts. The bone volume fraction was higher (p = 0.025) around the cyst then next to the cyst. CONCLUSIONS: The morphological findings that we found are only compatible with the previously reported simulation results of cyst growth in response to pressurized fluid, or pressurized fluid in combination with osteocyte death. It is therefore most likely that pressurized fluid plays a role in the pathoaetiology of cyst growth. A better understanding of cyst growth may improve treatment and prevent further cyst formation.