Knee subchondroplasty for management of subchondral bone cysts: a novel treatment method.

Knee subchondroplasty (SCP) is one of the most novel minimally invasive methods for treating bone marrow lesions. The literature suggests that it is safe, with few complications and good outcomes. However, no studies have documented its usage for managing large subchondral bone cysts. This article outlines a case report and details the pearls and pitfalls of SCP in treating large subchondral bone cysts. Our patient underwent arthroscopic debridement with medial femoral condyle SCP. Mild posterior extravasation of synthetic bone substitute was observed on Postoperative Day 1, which was immediately rectified on revision arthroscopy. Gradual escalation of weight bearing and good pain relief were subsequently achieved, and the patient has remained complication-free after two years. No further extravasation were observed on repeat radiography. SCP is a feasible temporising measure that may help to delay the need for bone allograft or immediate knee arthroplasty in younger patients while retaining function and delaying loss of productivity.

Hybrid suture technique vs simple suture technique for antero-inferior labral tears: Two years' clinical outcomes.

BACKGROUND: We previously reported a hybrid suture technique, wherein mattress and simple suturing are used to create Mason-Allen configuration, with low recurrence rates. This comparative study looking at the two years' clinical outcomes of arthroscopic anterior labral repair using the hybrid suture technique versus simple suture technique. METHODS: We identified 103 patients who underwent arthroscopic anterior labral repair from 2010 to 2015 with 2-year follow-up. The patients were categorized into two groups: hybrid suture technique (65 patients) and simple suture technique (38 patients). Clinical outcomes measures included UCLA shoulder score, Constant Shoulder Score, Numerical Pain Rating Scale, and Oxford Instability score. RESULTS: Mean age of the patients was 27.02 ±â€¯9.76 years (17-63), with 91 males and 12 females. At 24 months, both groups showed significant improvement in post-operative clinical scores compared to pre-operation. The patients in hybrid sutures technique demonstrated significant improvement in Constant Shoulder Score, UCLA shoulder score and Oxford Instability score compared to simple suture group at 3 months follow up. (121.98 ±â€¯21.05 vs 109.32 ±â€¯21.15, p < 0.05; 65.5 ±â€¯19 vs 57.4 ±â€¯17.6, p < 0.05; 27.3 ±â€¯5.7 vs 23.7 ±â€¯5.0, p < 0.05; 29.3 ±â€¯8.9 vs 33.4 ±â€¯8.2, p < 0.05). The postoperative recurrence rate was comparable between both groups (hybrid suture group 7.81% vs simple suture group 7.84%). CONCLUSIONS: Arthroscopic anterior labral repair with hybrid suture technique offers significant early improvements in clinical scores and low recurrence rate compared to simple suture technique at 2-year follow-up. LEVEL OF EVIDENCE: Level III; Retrospective Cohort Design; Treatment study.

Strain behavior of native and reconstructed medial patellofemoral ligaments during dynamic knee flexion - a cadaveric study.

BACKGROUND: Surgical reconstruction of the Medial Patello-Femoral Ligament (MPFL) has been recognized as an effective treatment for patients with instability despite conservative treatment. The purpose of this cadaveric study is to compare the strain patterns within the native and reconstructed single and double-bundle MPFL. This will help ascertain if the native biomechanics are restored with the reconstructions. METHODS: Twelve cadaveric knees were dissected and the native MPFL of each specimen was identified. The knees were subjected to dynamic flexion using a customized jig. Continuous strain measurements were taken for each knee from 0 to 120 degrees flexion and then back to full extension using differential variable reluctance transducers (DVRTs). The MPFL was then cut. Six single bundle and six double bundle MPFL reconstructions were performed using hamstring tendon grafts. The DVRTs were reattached to the grafts and strain measurements were retaken. Statistical analysis was performed using a paired t-test. RESULTS: Strain patterns of the native and reconstructed MPFL showed an increase in strain from 0 to 120 degrees of flexion except for the inferior bundle of the double bundle reconstruction. The strain patterns in the intact specimens were higher than the reconstructed MPFL through different degrees of knee flexion. In the double-bundle group, the superior graft had statistically significantly lower strains compared to the native MPFL with p-value <.05 at all flexion angles. The reconstructed inferior band showed loss of tension as the knee flexed. Higher strain with statistical significance (p-value <.05) was found in the single-bundle compared to the superior band of the double-bundle reconstruction at flexion angles less than 90 degrees. CONCLUSION: The strain variation at progressive angles of knee flexion is dissimilar between the native and reconstructed MPFL. The reconstructed MPFL exhibited non-physiological biomechanics with the inferior band losing tension. Although the single-bundle reconstruction shows a better strain profile compared to double-bundle reconstruction, the grafts are significantly stiffer than the native MPFL.