Shanmugam Karthikeyan

Microfracture for Acetabular Chondral Defects in Patients With Femoroacetabular Impingement Results at Second-Look Arthroscopic Surgery

Background: Microfracture is a proven technique to treat articular cartilage defects in the knee. However, there is little evidence in the literature to confirm the ability of microfracture to produce repair tissue in the hip joint. Purpose: The purpose of this study was to report the macroscopic and microscopic appearances of repair tissue after microfracture performed at hip arthroscopic surgery for isolated full-thickness acetabular cartilage defects in patients with femoroacetabular impingement (FAI). Study Design: Case series; Level of evidence, 4. Methods: Twenty patients who underwent arthroscopic surgery for FAI had a localized full-thickness acetabular chondral defect treated by microfracture and then underwent a later second-look hip arthroscopic procedure. The size of the full-thickness defect was measured at the primary arthroscopic procedure. A visual assessment of the extent and quality of repair tissue was performed at second-look arthroscopic surgery. Two patients also had a biopsy of the repair tissue, which was studied histologically. Results: At an average follow-up of 17 months, 19 of the 20 patients had a mean fill of 96% ± 7% with macroscopically good quality repair tissue. One patient had only a 25% fill with poor quality repair tissue. Histologically, the tissue was found to be primarily fibrocartilage with some staining for type II collagen in the region closest to the bone. Conclusion: Microfracture in the hip appears to be an effective technique that produces excellent coverage of the defect with good quality repair tissue on visual inspection and microscopic examination at an average follow-up of 17 months.

A double-blind randomised controlled study comparing subacromial injection of tenoxicam or methylprednisolone in patients with subacromial impingement

We have carried out a prospective double-blind randomised controlled trial to compare the efficacy of a single subacromial injection of the non-steroidal anti-inflammatory drug, tenoxicam, with a single injection of methylprednisolone in patients with subacromial impingement. A total of 58 patients were randomly allocated into two groups. Group A received 40 mg of methylprednisolone and group B 20 mg of tenoxicam as a subacromial injection along with lignocaine. The Constant-Murley shoulder score was used as the primary outcome measure and the Disability of Arm, Shoulder and Hand (DASH) and the Oxford Shoulder Score (OSS) as secondary measures. Six weeks after injection the improvement in the Constant-Murley score was significantly greater in the methylprednisolone group (p = 0.003) than in the tenoxicam group. The improvement in the DASH score was greater in the steroid group and the difference was statistically significant and consistent two (p < 0.01), four (p < 0.01) and six weeks (p < 0.020) after the injection. The improvement in the OSS was consistently greater in the steroid group than in the tenoxicam group. Although the difference was statistically significant at two (p < 0.001) and four (p = 0.003) weeks after the injection, it was not at six weeks (p = 0.055). Subacromial injection of tenoxicam does not offer an equivalent outcome to subacromial injection of corticosteroid at six weeks. Corticosteroid is significantly better than tenoxicam for improving shoulder function in tendonitis of the rotator cuff after six weeks.

Accuracy of Abduction-External Rotation MRA Versus Standard MRA in the Diagnosis of Intra-articular Shoulder Pathology

The goal of this study was to compare the accuracy of abduction-external rotation magnetic resonance arthrography (ABERMRA) with standard MRA in the diagnosis of intra-articular shoulder pathology.One hundred three consecutive patients undergoing preoperative direct MRA and subsequent arthroscopic examination were included in the study. Seventy-eight patients underwent standard MRA and 25 underwent ABERMRA. Specialist-trained musculoskeletal radiologists reported all scans, and attending shoulder surgeons performed all arthroscopies. Arthroscopic assessment revealed 11 partial-thickness rotator cuff tears, 3 full-thickness tears, 64 labral lesions (48 soft tissue and 16 significant bony), and 17 superior labrum anterior-posterior (SLAP) tears. The sensitivity/specificity for standard MRA was 0.56/0.99 for partial-thickness rotator cuff tears, 1.00/1.00 for full-thickness rotator cuff tears, 0.75/0.91 for soft tissue labral tears, 0.58/1.00 for significant bony glenoid lesions, and 0.50/0.91 for SLAP tears. Abduction-external rotation magnetic resonance arthrography increased the sensitivity/specificity to 1.00/0.85 for soft tissue labral tears, 0.75/1.00 for significant bony glenoid lesions, and 1.00/1.00 for SLAP tears, although it missed 2 of 2 partial-thickness rotator cuff tears.This study suggests that standard MRA is a valuable investigation tool for instability, SLAP tears, and rotator cuff tears, although limitations exist. Additional ABERMRA sequences appear to improve the diagnostic accuracy of soft tissue anterior and posterior labral tears, SLAP tears, and significant bony glenoid lesions and should be routinely requested by shoulder surgeons when ordering MRAs to obtain the maximum benefit from this invasive investigation.

A novel method of accurately calculating the radiological magnification of the hip

We have developed a novel method of calculating the radiological magnification of the hip using two separate radio-opaque markers. We recruited 74 patients undergoing radiological assessment following total hip replacement. Both the new double marker and a conventional single marker were used by the radiographer at the time of x-ray. The predicted magnification according to each marker was calculated, as was the true radiological magnification of the components. The correlation between true and predicted magnification was good using the double marker (r = 0.90, n = 74, p < 0.001), but only moderate for the single marker (r = 0.50, n = 63, p < 0.001). The median error was significantly less for the double marker than for the single (1.1% vs 4.8%, p < 0.001). The double marker method demonstrated excellent validity (intraclass correlation coefficient = 0.89), in contrast to the single marker (0.32). The double marker method appears to be superior to the single marker method when used in the clinical environment.

Microvascular blood flow in normal and pathologic rotator cuffs

BACKGROUND Microvascular blood flow in the tendon plays an important role in the pathogenesis of rotator cuff abnormalities. There are conflicting views about the presence of a hypovascular zone in the supraspinatus tendon. Besides, no studies have looked at the pattern of blood flow around a partial-thickness tear. Our aim was to measure microvascular blood flow in normal and a range of pathologic rotator cuff tendons using laser doppler flowmetry. METHODS A total of 120 patients having arthroscopic shoulder surgery were divided into 4 equal groups on the basis of their intraoperative diagnosis: normal rotator cuff, subacromial impingement syndrome, and partial-thickness or full-thickness rotator cuff tear. Microvascular blood flow was measured at 5 different regions of each cuff using a laser doppler probe. The values were compared to assess variability within and between individuals. RESULTS Total blood flow was greater in the normal rotator cuff group compared with the groups with pathologic rotator cuffs, with the largest difference seen in the subacromial impingement group. Within individuals, blood flow was highest at the musculotendinous junction and lowest at the lateral insertional part of the tendon. Among groups, the blood flow was significantly lower at the anteromedial and posteromedial cuff in the groups with impingement and full-thickness tears compared with the group with normal cuff. CONCLUSION Real-time in vivo laser doppler analysis has shown that microvascular blood flow is not uniform throughout the supraspinatus tendon. Blood flow in the pathologic supraspinatus tendon was significantly lower compared with the normal tendon.

Accuracy of high-resolution ultrasonography in the diagnosis of articular-sided partial thickness rotator cuff tears

Background The present study aimed to assess the accuracy of high-resolution ultrasonography in the detection of articular-sided partial thickness rotator cuff tears. Methods Two-hundred and forty-six shoulders of 245 patients underwent ultrasonography and subsequent shoulder arthroscopy. All scans were performed by an experienced specialist musculoskeletal radiologist and arthroscopies were carried out by a single surgeon. Results Fifty-eight partial thickness tears (of which 56 were articular-sided) were found at arthroscopy. Of the remaining shoulders, 90 had full thickness tears and 98 had intact rotator cuffs. Ultrasonography correctly identified 21 of 56 articular-sided tears as partial thickness tears. It had a sensitivity of 7%, a specificity of 98% and an accuracy of 74% for the diagnosis of articular-sided partial thickness tears. If a full thickness tear was considered as a true positive, the sensitivity increased to 89%, specificity to 98% and accuracy to 96%. Discussion Ultrasonography is not sufficiently accurate to diagnose articular-sided partial thickness tears. A higher accuracy can be achieved if a full thickness tear is considered a positive finding. Ultrasonography should not be considered a first line investigation for a clinically suspected partial thickness rotator cuff tear. An articular-sided partial thickness rotator cuff tear should be considered in all patients undergoing an arthroscopic rotator cuff procedure.

Normal and Pathological Arthroscopic View in Hip Arthroscopy

Arthroscopy of the hip involves examination of two areas of the joint, often called the central and peripheral compartments. The central compartment is the potential space between the articular cartilage of the femoral head, and that of the acetabulum, and is bounded by the acetabular labrum. The peripheral compartment is the intra-capsular space lateral to the labrum and surrounding the femoral neck.