An anatomical study on the Stener-type lesion of the radial collateral ligament of the metacarpophalangeal joint of the thumb

Radial Collateral Ligament Injuries of the Thumb Metacarpophalangeal Joint

PURPOSE OF REVIEW

Injuries to the radial collateral ligament (RCL) of the thumb are thought to be relatively uncommon, especially when compared to the ulnar collateral ligament. However, the radial collateral ligament is increasingly recognized as critical for the overall stability of the thumb metacarpophalangeal joint. This article sets out to provide a comprehensive review of RCL injuries of the thumb MCP joint, including epidemiology, biomechanics, diagnosis, and treatment.

RECENT FINDINGS

Although traditionally thought to respond well to conservative management, especially when compared to injuries to the ulnar collateral ligament, there is mounting evidence that chronic RCL injury leads to thumb metacarpophalangeal joint instability and can accelerate post-traumatic joint degeneration. Thus, much of the recent literature details surgical treatment options for radial collateral ligament injury, including repair and reconstruction. While incomplete tears of the thumb RCL respond well to immobilization, complete tears should generally be treated with operative management, either direct repair or anatomic reconstruction, depending on tissue quality. Even subacute and chronic injuries may be amenable to direct repair, with good to excellent outcomes, including in high-demand patient populations, such as professional athletes.

Early vs late surgical treatment of radial instability of the thumb metacarpophalangeal joint. A retrospective cohort study

There is no clear evidence in the literature whether treating thumb radial collateral ligament (RCL) injury in the acute phase improves outcome. The purpose of the present study was to compare the clinical and radiological results of RCL repair in acute and chronic settings. Fourteen patients were included. Clinical range of motion (ROM) of the thumb, Kapandji score and radiological parameters were compared pre- and post-operatively to the contralateral uninjured thumb (control group) to evaluate the results of the surgical technique. Patients were then divided into two groups according to early versus late repair and outcomes were compared between the two groups and the control group. Preoperatively, mean spontaneous angle between first metacarpal (M1) and proximal phalanx (P1) (spontaneous M1P1 angle), ulnar stress M1P1 angle, ROM and Kapandji score differed significantly between injured and uninjured sides. Postoperatively these parameters for the injured side improved, reaching values similar to those on the uninjured side, especially with acute phase treatment; late treatment also tended to provide clinical improvement in ROM, Kapandji score and ulnar stress angle, but with significant improvement only for spontaneous deviation of the thumb. This study showed the late and immediate repair of the RCL of the thumb both gave good results, with slightly better outcome with acute phase repair. LEVEL OF EVIDENCE: Therapeutic, Level III.

Radial collateral ligament repair of the thumb: long-term outcomes and predictive factors of postoperative deficits

BACKGROUND

The thumb's radial collateral ligament (RCL) plays an important role in stabilizing the first metacarpophalangeal joint (MCP-1). RCL injuries are rare and treatment recommendations are inconsistent in the current literature. The aim of this study was to report on long-term outcomes following surgical repair of thumb RCL tear and to identify prognostic risk factors for treatment failure.

METHODS

Patients with RCL tear from 10/1998 to 10/2019 were included in the present retrospective single center cohort study. In follow-up visits, participants were assessed regarding pain, range of motion and strength as well as with disability of shoulder, arm and hands (DASH), and the Short-Form 36 (SF36) questionnaires. Finally, predictive factors of postoperative deficits were identified.

RESULTS

43 patients fulfilled inclusion criteria. Median age was 43.5 years (range 18-80 years). The most frequent mechanism of injury was a fall or impact. Bony avulsions were identified in 46.5% (20/43). Time from injury to surgery was 12 days (0-276 days). One Stener-like lesion was observed intraoperatively among our patients. After surgical repair, the MCP-1 joint was stable in every patient. Mean time to follow-up was 5.3 years (1 month to 17 years). Persistency of pain in the MCP-1 joint was reported by 11 patients. Postoperative averaged score was 3.75 on DASH and 44.96 on SF36, respectively. The average grip and pinch strength was 32.7 kg and 8.37 kg, respectively. Predictive factors of postoperative deficits were delay of surgery of > 3 weeks (OR 10.72, p 0.017) and palmar subluxation prior to surgery (OR 8.86, p 0.019).

CONCLUSION

Long-term follow-up has proven that surgical repair of RCL enables the patient to regain adequate stability and strength of the MCP-1 joint and minimizes disability. Predictive risk factors of pain persistency after surgery are surgical delay and palmar subluxation of the MCP-1 joint.