Relative Motion Splinting: Indications and Results

Abstract

Relative motion splinting is a simple way to reduce tension on extensor and flexor tendons after an injury or surgery. The affected finger is placed in increased extension (relative motion extension splint, RMES) or flexion (relative motion flexion splint, RMFS) relative to the neighbouring fingers, allowing for active tendon gliding within a protected range of motion at the site of repair or injury. While originally introduced for the treatment of extensor tendon injuries, the concept of relative motion splinting is now being used for a growing number of indications. It is characterised by a compact splint design that enables early return to work with minimal restrictions in daily activities. This article provides an overview of the most common applications and clinical outcomes.

Keywords

Hand therapy - Relative Motion Splint - splint design - extensor tendon aftercare

Publication History

Received: 14 April 2025

Accepted: 30 April 2025

Article published online:
02 July 2025

• References

• 1 Howell JW, Peck F. Rehabilitation of flexor and extensor tendon injuries in the hand: current updates. Injury 2013; 44: 397-402
• 2 Howell JW, Merritt WH, Robinson SJ. Immediate controlled active motion following zone 4-7 extensor tendon repair. J Hand Ther 2005; 18: 182-190
• 3 Merritt WH, Wong AL, Lalonde DH. Recent Developments Are Changing Extensor Tendon Management. Plast Reconstr Surg 2020; 145: 617e-628e
• 4 Sharma JV, Liang NJ, Owen JR. et al. Analysis of relative motion splint in the treatment of zone VI extensor tendon injuries. J Hand Surg Am 2006; 31: 1118-1122
• 5 Merritt WH. Relative motion splint: active motion after extensor tendon injury and repair. J Hand Surg Am 2014; 39: 1187-1194
• 6 Hirth M, Bennett K, Mah E. et al. Early return to work and improved range of motion with modified relative motion splinting: A retrospective comparison with immobilization splinting for zones V and VI extensor tendon repairs. Hand Therapy 2011; 16: 86-94
• 7 Newport ML, Tucker RL. New perspectives on extensor tendon repair and implications for rehabilitation. Journal of Hand Therapy 2005; 18: 175-181
• 8 Merritt WH, Howell J, Tune R. et al. Achieving immediate active motion by using relative motion splinting after long extensor repair and sagittal band ruptures with tendon subluxation. Operative Techniques in Plastic and Reconstructive Surgery 2000; 7: 31-37
• 9 Evans RB, Burkhalter WE. A study of the dynamic anatomy of extensor tendons and implications for treatment. J Hand Surg Am 1986; 11: 774-779
• 10 Robinson SJ, Rosenblum NI, Merritt MH. A new splint design for immediate active motion following extensor tendon repair. Ninth Annual Meeting of the American Society of Hand Therapists. 1986 New Orleans, Louisiana
• 11 Kaplan EB. Functional and Surgical Anatomy of the Hand. 2. Aufl. Lippincott: 1965
• 12 Zancolli E. Structural and Dynamic Bases of Hand Surgery. 2. Aufl. Lippincott: 1979
• 13 Lalonde DH, Flewelling LA. Solving Hand/Finger Pain Problems with the Pencil Test and Relative Motion Splinting. Plast Reconstr Surg Glob Open 2017; 5: e1537
• 14 Feehan LM, Ewald SG. Relative motion orthoses: A five-question decision making tool for thinking beyond thermoplastics. J Hand Ther 2023; 36: 479-485
• 15 Schwartz DA. Relative motion orthoses: fabrication tips. J Hand Ther 2023; 36: 486-493
• 16 Hirth MJ, Howell JW, O'Brien L. Relative motion orthoses in the management of various hand conditions: A scoping review. J Hand Ther 2016; 29: 405-432
• 17 Thomas D, Moutet F, Guinard D. Postoperative management of extensor tendon repairs in zones V, VI, and VII. J Hand Ther 1996; 9: 309-314
• 18 Saldana M. Comparison of the ‘Merritt’ splint to dynamic splinting following extensor tendon repair. American Association for Hand Surgery Annual Meeting Proceedings. 1997 Phoenix, AZ
• 19 Catalano LW, Gupta S, Ragland R. et al. Closed treatment of nonrheumatoid extensor tendon dislocations at the metacarpophalangeal joint. J Hand Surg Am 2006; 31: 242-245
• 20 Peelman J, Markiewitz A, Kiefhaber T. et al. Splintage in the treatment of sagittal band incompetence and extensor tendon subluxation. J Hand Surg Eur Vol 2015; 40: 287-290
• 21 Evans RB. Early active short arc motion for the repaired central slip. J Hand Surg Am 1994; 19: 991-997
• 22 Howell J, Merritt W. Relative Motion Orthoses: The Concepts and Application to Hand Therapy Management of Finger Extensor Tendon Zones III and VII Repairs, Acute and Chronic Boutonniere Deformity and Sagittal Band Injury. In Rehabilitation of the Hand and Upper Extremity. 7. Aufl. Elsevier; 2018
• 23 Steichen JB, J. S. Results of surgical treatment of chronic boutonniere deformity: An analysis of prognostic factors. In Difficult problems in hand surgery,. 1. Aufl. CV Mosby; 1982: 62-69
• 24 Newington L, Ross R, Howell JW. Relative motion flexion splinting for the rehabilitation of flexor tendon repairs: A systematic review. Hand Ther 2021; 26: 102-112
• 25 Henry SL, Howell JW. Use of a relative motion flexion orthosis for postoperative management of zone I/II flexor digitorum profundus repair: A retrospective consecutive case series. J Hand Ther 2020; 33: 296-304