Purpose: During surgery for repair of rotator cuff tears, some authors always associate tenotomy-tenodesis of the long head of the brachial biceps. Others decide as a function of the gross aspect of the tendon and its position in relation to the bicipital groove. It is a classical notion the preservation of the long head of the brachial biceps is a cuase of persistent pain in operated shoulders. This study was conducted to search for a histological validation of the decision to perform tenotomy.
Material and methods: Fifty tendons of the long head of the brachial biceps presented a thick and inflammatory aspect with or without subluxation during 68 procedures to repair recent rotator cuff tears (23 men, 27 women, mean age 53.5 years). Tenodesis of the long head of the brachial biceps was associated with proximal tenotomy. The histological examination concerned the most proximal centimeter of the tendon. Four parameters were studied: two concerned the tendon (organisation of the collagen network and aspect of the interstitial connective tissue), two concerned the synovial border (sub-synoviocytic layer and synovial mesothelium). Sixteen tendons which appeared perfectly healthy were harvested from cadaver shoulders to determine the normal aspect of histological parameters (parallel and cohesive orientation of the collagen network, absence of hypertrophic interstitial connective tissue, thin subsynovio-cytic layer and pluristratified synovial mesothelium).
Results: The tendon. The collagen bundles were oriented in 32 cases but thick in 40 and dissociated in 47. Microscopic signs of fissuration or intratendinous tears were present in 17 cases. The tendinous connective tissue was oedematous in 49 cases, presenting fibroblastic hyper-cellularity in 37 and hypervascularity in 43. Scar-like fibrosis was observed in 28 cases. The synovial layer was regular in 11 tendons and clearly thickened in 26 with a mixed irregular aspect in the others. The subsynoviocytic layer was thick in 33 tendons with signs of hypervascularity or hypercellularity in 12. The synovial mesothelium was paucistratifed in 23 cases, thick in 12, and regular in 15. Lesions had an inflammatory aspect and were intense in 26 cases. Degenerative lesions were observed in 21 tendons. These four histological parameters demonstrated that the lesions were advanced and associated with degenerative sclerosis with reactional synovitis in 30 cases, moderate combined lesions in 13, tendon and synovial inflammation alone in four, and advanced degenerative lesions of the tendon and the synovial in six.
Discussion: Histological lesions of the long head of the brachial biceps tendon are generally degenerative and irreversible while most synovial lesions are reversible inflammatory reactions. The zones of intratendinous fibrosis, vascularity and weak or absent cellularity constitute the anatomic conditions before tendon tears in chronic tendinopathy. This histological study confirmed the validity of the intra-operative decision for tenodesistenotomy of the long head of the brachial biceps in 46 (92%) of the cases. The oedematous and fissu-rated aspect of the tendon appeared to be a reliable criteria while inflammatory synovitis, which surrounds the tendon, does not constitute in itself a formal argument in favour of tendon sacrifice.
