The purpose of this feasibility pilot study is to determine the effectiveness of Relative Motion Orthosis (RMO) in regaining finger range of motion compared to standard care in patients diagnosed with Proximal Interphalangeal (PIP) stiffness with an extension lag secondary to finger injury. Participants will be enrolled and randomized into groups receiving either standard conservative interventions or standard interventions in addition to the RMO. The primary endpoint is to evaluate the efficacy of relative motion orthosis in PIP ROM using clinical scoring and physical exam findings.

Inclusion Criteria:

• Age range 18-80
• Any gender
• Any Proximal Interphalangeal (PIP) injury that causes reduced PIP Active Range of Motion (AROM) in extension
• Right or left hand injury
• Level of Chronicity (4 weeks - 6 months)
• Able to follow instructions

Exclusion Criteria:

• PIP with hard end feel (feels they need serial casting) - level of chronicity
• Any digital nerve injury / skin laceration that can prevent the patient from using the orthosis
• Severe arthropathy
• Literacy deficits: patients need to be able to follow verbal and written instructions independently to minimize risks and improve outcomes from care.

The de-identified participant data from the final research dataset will be shared to achieve aims in the approved proposal beginning 9 to 36 months after publication or as required by a condition of awards or supporting agreements, provided the requesting investigator executes a data use agreement with NYU Langone Health. This instance of data sharing will also require separate IRB review as well as review from NYU Langone's Data Sharing Strategy Board (DSSB). Requests should be directed to: Natalia.Ruiz@nyulangone.org. The protocol and statistical analysis plan will be posted on Clinicaltrials.gov only as required by federal regulation or supporting awards and agreements.