The inflamed biceps tendon as a pain generator in the shoulder: A histological and biomolecular analysis

INTRODUCTION

The long head of the biceps (LHB) is often resected in shoulder surgery. However, its contribution to inflammatory processes in the shoulder remains unclear. In the present study, inflamed and noninflamed human LHBs were comparatively characterized for features of inflammation.

MATERIALS AND METHODS

Twenty-two resected LHB tendons were classified into inflamed ( n = 11) and noninflamed ( n = 11) samples. For histological examination, samples were stained with hematoxylin eosin, Azan, van Gieson, and Masson Goldner trichrome. Neuronal tissue was immunohistochemically visualized. In addition, specific inflammatory marker gene expression of primary LHB-derived cell cultures were analyzed.

RESULTS

Features of tendinopathy, such as collagen disorganization, infiltration by inflammatory cells, neovascularization, and extensive neuronal innervation were found in the tendinitis group. Compared to noninflamed samples, inflamed LHBs showed a significantly increased inflammatory marker gene expression.

CONCLUSION

Structural and biomolecular differences of both groups suggest that the LHB tendon acts as an important pain generator in the shoulder joint. These findings can, on the one hand, contribute to the understanding of the biomolecular genesis of LHB tendinitis and, on the other hand, provide possibilities for new therapeutic approaches.

[Osteotomies of the distal tibia]

OBJECTIVE

Restoration of physiological alignment of the distal tibia and thereby restoration of physiological loading of the ankle joint; joint preservation in asymmetric degenerative arthritis of the ankle.

INDICATIONS

Congenital deformities of the distal tibia; acquired deformities of the distal tibia; asymmetric degenerative arthritis with partially preserved cartilage.

CONTRAINDICATIONS

Absolute contraindications comprise severe nicotine abuse, Charcot arthropathy, peripheral polyneuropathy, relevant peripheral arterial vessel disease, poor local soft tissue condition, acute infection and extensive cartilage damage grade 3-4 in the Outerbridge classification in the complete joint.

SURGICAL TECHNIQUE

Medial and lateral open and closed wedge osteotomies and dome osteotomies of the distal tibia are used, and shortening, lengthening and derotating osteotomies of the fibula.

POSTOPERATIVE MANAGEMENT

For 6 weeks, 15-20 kg partial weight-bearing in a below knee cast or a walker orthosis; full weight-bearing depending on osseous healing after 9-12 weeks postoperatively.

RESULTS

Between July 2012 and May 2017, 15 patients (10 men, 5 women) underwent a supramalleor osteotomy. Average age was 41.8 years (range 17-63 years) and the retrospective average follow-up was 28.7 months (range 3-47 months). Mean preoperative AOFAS (American Orthopaedic Foot and Ankle Society) hindfoot score was 54.3 (range 26-86) and postoperatively a mean of 74.2 (44-100). Preoperatively, 9 patients had varus malalignment and 6 patients valgus malalignment; overall, 4 patients developed complications requiring surgical intervention (26.7%). Osteosynthetic material was removed in 60% of the patients.

[Refixation of the biceps tendon onto the radial tuberosity using two suture anchors]

OBJECTIVE

Reinsertion of the distal biceps tendon onto the radial tuberosity restoring full force of flexion and supination.

INDICATIONS

Distal biceps tendon avulsion from the radial tuberosity. Acute and chronic tears with a tendon stump, which can be mobilized and reduced to the radial tuberosity in flexion and supination.

CONTRAINDICATIONS

Tears of the musculotendinous junction. Chronic distal biceps tendon tears with wide retraction and the need for tendon graft augmentation. Severe atrophy of the biceps muscle.

SURGICAL TECHNIQUE

In supination, the skin is incised longitudinally for 4 cm, centered over the medial border of the radial tuberosity. Incision starts 2 cm distal from the humeroradial joint line. Bluntly the distal biceps tendon stump is found and mobilized. Preparation and debriding of the radial tuberosity sparing neurovascular structures. Crossing vessel branches are ligated, if needed. Positioning of two spreading anchors into the radial tuberosity and reinsertion of the tendon stump.

POSTOPERATIVE MANAGEMENT

Adjustable elbow movement orthosis adapted to tendon quality and tissue tension for 6 weeks without active flexion or supination. Degree of extension is gradually increased by 20° every 2 weeks. After orthosis treatment is finished after 6 weeks, flexion and supination with weights is not allowed for another 6 weeks.

RESULTS

In a retrospective study of 30 patients with a mean follow-up of 45 months (range 15-80 months), the clinical outcome was good or excellent in 99% of cases. On average, a Mayo Elbow Performance Score of 93 points (range 65-100 points) and a QuickDash of 5 points (range 0-39 points) were achieved.

Medially based anterior capsular shift of the glenohumeral joint. Passive range of motion and posterior capsular strain

The effect of a medially based anterior capsular shift on translational and rotational range of motion and posterior capsular strain was investigated in an in vitro model. Six cadaveric shoulders were tested in a robot-assisted shoulder simulator. Translational and rotational range of motion were reduced by the capsular shift, particularly with the shoulder at higher elevation angles. At 60 degrees of elevation, anterior translation was decreased 1.9 +/- 2.9 mm, and posterior translation was decreased 2.3 +/- 6.2 mm. External rotation was decreased 11.5 degrees +/- 10.2 degrees, and internal rotation was decreased 8.9 degrees + 5.7 degrees. Posterior capsular strain change was dependent on elevation angle. At 30 degrees of elevation, strain tended to increase 5.0% +/- 7.3% in the inferior aspect and 2.9% +/- 2.6% in the superior aspect, with no change detected in the medial aspect. At 60 degrees of elevation, strain increased 6.6% +/- 8.0%, 3.2% +/- 2.6%, and 4.4% +/- 3.5% in the inferior, middle, and superior aspects, respectively. Our results support the use of the medially based anterior shift for shoulders with anterior-inferior instability or multidirectional instability with posterior involvement.