Summary

Prospective study comparing Inlay Vs Onlay Techniques for Distal Biceps Brachii TendonTenodesis and showing both techniques give excellent functional outcome with no re-tears, good ROM and no long-term complications. Further studies should assess strength using a dynamometer of these two techniques.

Abstract

Introduction

Distal biceps tendon ruptures are commonly seen after excessive eccentric tension as the arm is forced from a flexed position affecting strength and function. The aim of surgery is to internally fix the distal biceps tendon onto the radial tuberosity to gain maximum flexion and supination strength. The aim of the study is to compare two tenodesis techniques: inlay technique (also called the tension-slide technique) with the BicepsButton™ (Arthrex, Florida, Naples, USA) vs onlay technique using Q-FIX 1.8mm All Soft Tissue Anchors™ (Smith & Nephew, Watford, UK) and assess intra-operative / surgical timings, post-operative PROMs , range of motion and complications.

Methods

Distal biceps tenodesis using onlay and inlay techniques performed by a single surgeon were reviewed from a prospectively collected database from 2020 to 2024. Patient demographics, time to surgery and mechanism of surgery were noted. Preoperative and post-operative PROMs were compared and included the following: Pain VAS score, ADL elbows score, overall ASES score, SANE score and qDASH. Post-operative Range of motion and complications were also recorded.

Results

A total of 40 patients underwent distal biceps tenodesis (20 inlay vs 20 onlay). All patients were male and 81 % were right hand dominant with 57% had injury on the dominant side. Mean age for inlay group was 47 years  10.3 (range 25-66) and onlay group was 42 years  11.4 (range 25-60). Mean time to surgery from injury for inlay group was 19.7 days  11 (range 6-42) and for onlay was 14.3 days  6.5 (range 4-26).
Mean surgical timing for inlay group was 77.7 minutes  20.5 (range 44-114) and for the onlay group was 79.5 minutes  20.5 (range 49-114). Mean follow-up was 21.8  7.8 months (12-40). On follow-up, mean ASES score of inlay group was 99.1  1 (98-100) and onlay group was 97.2  4.9 ( 85-100) while improvement was 38.8  26.7( 2-75) in inlay group and 41.1  7.8 ( 30-54) on onlay group. qDASH score was 2.2  2.86 (0-6.8) for the inlay group and 2.27  5.6 (0-16) for the onlay group.
Post-operatively patients gave a global rating of 94.65%  6 (85-100) for inlay and 90  8.6 (70-100) for the onlay group. Overall post-operative health state was 86.6  10.3 (70-100) for the inlay group and 86.6  13.2 (70-100) for the onlay group. Onlay group achieved better range of motion in terms of flexion and complete extension. 1 patient in each group had posterior interossei nerve neuropraxia secondary to retractors, both of which recovered on follow-up by 6-10weeks. Patient reported outcomes were analyzed using statistical software.

Conclusion

Both onlay and inlay give excellent functional outcome with no re-tears, good ROM and no long-term complications. Further studies should assess strength using a dynamometer of these two techniques.

Keywords: Distal biceps repair, Elbow scores, Inlay and onlay technique, BicepsButton™, Q-FIX 1.8mm All Soft Tissue Anchors™, Distal Biceps Brachii Tendon Tenodesis