Boutonniere Deformity of the Proximal Interphalangeal Joint in a Young, Active Female Patient: A Nonstandard Surgical Procedure

One of the key elements of post-traumatic osteoarthritis treatment is not only pain relief but also the return of joint function close to pre-injury levels. This is particularly important for young and physically active individuals. Unfortunately, the ability to return to satisfactory proximal intraphalangeal joint mobility after surgical treatment is often limited. This article describes the treatment of a young, active female patient who, several years ago, suffered a proximal interphalangeal (PIP) joint injury in her fifth finger following a fall from a height. Initially, the patient was treated at another hospital using open reduction internal fixation and stabilization with two Kirschner wires. A complication of this treatment was a "boutonniere" finger deformity with stiffening of the phalanx in the position of flexion contracture of 80° and the presence of finger pain with a numerical rating scale (NRS) score of 6. X-ray examination revealed initial degenerative changes in the joint surface of the proximal phalanx. The patient was classified for joint replacement using a cementless CapFlex hemiarthroplasty. A follow-up examination was performed after six months, which revealed an unsatisfactory clinical outcome because the total range of motion was 10° (extension deficit: 80°; flexion range: 90°) and the boutonniere deformity was still present. Pain intensity was 0 on the NRS scale. Due to the patient's active lifestyle, a joint decision was made to qualify the patient for revision surgery using a 3S ORTHO semiconstrained prosthesis. A follow-up examination performed eight weeks after the surgery showed correction of the butenoid deformity, improvement of the flexion range of motion to 50°, with limitation of the active extension movement (extension deficit reached 15°). Pain intensity was rated 0 on the NRS scale. After the follow-up examination, the patient was referred for additional specialized physiotherapy treatments, including post-isometric muscle relaxation, manipulation exercises, and whirlpool massage, to further improve the range of motion and dexterity of the treated hand. Additional physiotherapy treatments resulted in further improvement in range of motion and functional efficiency. Arthroplasty of the PIP joint using a cementless CapFlex hemiarthroplasty corrected the boutonniere deformity. At follow-up, a significant degree of flexion contracture developed. Revision surgery involving implantation of a 3S ORTHO prosthesis improved the flexion range of motion. The extension range of motion did not return to normal. According to the patient, the regained hand function met her expectations and allowed her to return to her previously performed activities. These results reflect the early follow-up period.