Determining the Minimal Clinically Important Difference on the Oxford Shoulder Instability Score in Patients Undergoing Arthroscopic Bankart Repair for Shoulder Instability.

BACKGROUND: The literature on minimal clinically important differences (MCIDs) for patient-reported outcome measures assessing shoulder instability is limited, with none addressing the Oxford Shoulder Instability Score (OSIS). The OSIS was developed to provide a standardized method for assessing shoulder function after surgery for shoulder instability, and previous studies have demonstrated its high reliability, low interrater variability, and ease of administration. PURPOSE: To identify the MCID for the OSIS after arthroscopic Bankart repair for recurrent shoulder instability. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A longitudinally maintained institutional registry was queried for patients who underwent arthroscopic Bankart repair from 2010 to 2016 for recurrent shoulder instability secondary to a Bankart lesion without significant glenoid bone loss. The OSIS was completed preoperatively and at 1 year postoperatively. Patients were categorized into "expectations met" and "expectations unmet" groups using a questionnaire evaluating expectation fulfilment. The MCID of the OSIS at 1 year was calculated using 3 anchor-based approaches and a distribution-based approach. The 3 anchor-based approaches comprised (1) simple linear regression analysis, (2) receiver operating characteristic curve analysis, and (3) calculation of mean differences in change for the OSIS between the "expectations met" and "expectations unmet" groups. RESULTS: The study cohort comprised 68 men and 11 women aged 29.9 ± 12.7 years (mean ± SD). Duration of follow-up for all patients exceeded 1 year. The MCIDs for the OSIS based on the 4 calculation approaches yielded a narrow range of values, ranging from 7.7 to 8.5 for the anchor-based methods and 8.6 for the distribution-based method. CONCLUSION: Study results indicated that patients with recurrent shoulder instability without significant bone loss who undergo primary arthroscopic Bankart repair and have at least 8.6 points of improvement on their OSIS experience a clinically significant change at 1 year postoperatively.

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.

Unicompartmental knee arthroplasty in patients with Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) adversely affects physical function after joint replacement. The biomechanical advantages of unicompartmental knee arthroplasty (UKA) may be particularly beneficial for these patients who suffer from gait and kinetic abnormalities. We aimed to describe the functional outcomes, complications and survivorship after UKA in patients with PD. METHODS: Ten patients (11 knees) undergoing primary fixed-bearing UKA for medial osteoarthritis were studied. Knee Society Knee (KSKS) and Function Scores (KSFS), as well as the Short-Form-36 (SF-36) Mental (MCS) and Physical Component Scores (PCS) were assessed preoperatively, at six months and at two years postoperatively. Complications, survivorship and all-cause mortality were analyzed. RESULTS: No perioperative complications occurred. Length of stay was 5 ± 2 days and no patients were discharged to rehabilitation or readmitted. Nine of 11 knees had a flexion contracture preoperatively and this remained unchanged at two years. KSKS and SF-36 PCS improved significantly. However, there was no improvement in KSFS or SF-36 MCS. All patients achieved minimal clinically important difference for KSKS, six of 11 for KSFS and nine of 11 for SF-36 PCS. At mean 10 ± 5 years, there was one revision for progression of osteoarthritis. Seven of 10 patients progressed in Hoehn and Yahr stage and only three were able to ambulate independently at last follow-up. CONCLUSIONS: Patients suffering from osteoarthritis and PD can experience a substantial improvement in knee pain with low morbidity after UKA. However, the improved kinematics of UKA did not translate to an improved range of motion or knee function postoperatively.

Induced Membrane Bone Grafting Technique for Treatment of Large Postinfectious Acetabular Bone Defects.

Management of large acetabular bone defects is challenging. The Masquelet technique has successfully reconstructed segmental defects in long bones arising from trauma, tumors, or infection but not been described for large acetabular defects. We present 3 cases of large acetabular bone defects arising from chronic prosthetic joint infection, treated via a novel induced membrane bone grafting technique, drawn from the Masquelet technique. All cases showed satisfactory clinical and radiological outcomes at midterm follow-up. This technique holds promise and can be an alternative means when treating large acetabular bone defects.

Rehabilitation outcomes following revision for failed unicompartmental knee arthroplasty.

BACKGROUND: To investigate the post-operative outcomes of a revised UKA to a TKA compared to a primary TKA. METHODS: 33 revised UKA were matched to primary TKA and assessed using SF-36, Oxford Knee Scores (OKS) and Knee Society Scores (KSS). RESULTS: Both cohorts attained statistically similar SF-36 scores (p > 0.05). KSS improved by 51.12 in rev-UKA and 50.25 in primary TKA (p = 0.977) at 2 years. OKS scores were similar at 6 months (p = 0.094) and 2 years (p = 0.235).. INTERPRETATION: Revision of UKA does not require a longer period of rehabilitation to achieve satisfactory return to function.