Midcarpal osteoarthritis

Anatomy: Where is the midcarpal joint?

The wrist is composed of two main joint levels: the radiocarpal joint (between the radius and the proximal carpal row) and the midcarpal joint (between the proximal and distal carpal row). The proximal bones are scaphoid, lunate and triquetrum; lie distally, among other things. Head bone (capitatum) and hook bone (hamatum).

• Midcarpal joint: contact surfaces v. a. between capitate and lunate (capitolunary) and between hamate and triquetrum.
• Important ligament structures: scapholunate and lunotriquetral ligaments, plus midcarpal interosseous and extrinsic ligaments.
• Function: Power transmission from the hand to the forearm, fine adjustment of flexion/extension and lateral movements, stabilization under grip load.

The capitolunate part of the joint in particular is heavily stressed in degenerative collapse patterns (e.g. SLAC). Overload and ligament insufficiency can change the pressure distribution - the result is cartilage wear in the midcarpal joint.

What is midcarpal osteoarthritis?

Midcarpal osteoarthritis is the wear and tear of the cartilage in the middle carpal joint. The contact surfaces between the capitate and lunate are often affected (capitolunar arthrosis). The symptoms differ from radiocarpal arthrosis: pain is described more centrally-dorsally, often increased by pressure (e.g. push-ups, propping up, screwing work) and by repeated flexion/extension movements.

• Primary degenerative is rare; more often post-traumatic or post-unstable.
• Can be part of a SLAC/SNAC history.
• Often occurs in fits and starts, with periods of rest and increases in stress.

Symptoms: How do I recognize midcarpal osteoarthritis?

• Pain on the back of the hand (central or ulnar), sometimes stabbing with certain movements.
• Start-up pain and morning stiffness, which may improve slightly after a short period of exercise.
• Decrease in grip strength, difficulty opening bottles, carrying bags, or supporting body weight.
• Pain provocation with maximum wrist extension (e.g. push-ups) or repeated screwing/hammering.
• Occasionally a painful “click” or “clunk” indicating accompanying instability.
• In advanced stages, pain at rest, swelling and restricted movement.

Causes and risk factors

Midcarpal osteoarthritis usually arises from changes in kinematics as a result of ligament injuries or bony healing disorders. This shifts the load distribution in the wrist, which can overload the cartilage in the midcarpal joint.

• SLAC (Scapholunate Advanced Collapse) for scapholunate ligament insufficiency.
• SNAC (Scaphoid Nonunion Advanced Collapse) for scaphoid nonunion.
• Post-traumatic changes after distal radius fracture or carpal fractures.
• Chronic overload due to repetitive activities, vibration, weight training with strong wrist extension.
• Misalignments, variances (e.g. ulnar variance), rarely inflammatory systemic diseases.

Risk factors include older age, previous accidents, manual work, sports with supporting weight, smoking (impairs tissue healing) and inadequate rehabilitation after ligament or bone injuries.

Diagnostics: This is how we proceed

Precise diagnosis is crucial to assess the location of the osteoarthritis (radiocarpal vs. midcarpal) as well as accompanying factors such as instability. In addition to a careful anamnesis, we check mobility, carry out provocation tests and plan targeted imaging.

• Clinic: Pain on palpation dorsally central, pain on extension/axial load. Signs of instability (e.g. midcarpal clunk).
• X-ray in at least 2 planes; If necessary, a “clenched fist” image to assess instability.
• Assessment of degenerative patterns (SLAC/SNAC stages) and joint space narrowing in the midcarpal compartment.
• CT for detailed joint surface and bone assessment, especially preoperatively.
• MRI to assess cartilage, bone marrow edema and ligaments; helpful for unclear findings.
• Differential diagnoses: radiocarpal arthrosis, STT arthrosis, Kienböck's disease, Preiser's disease, tendinopathies, nerve constriction syndromes.

Conservative therapy: step-by-step plan first

The goal of conservative treatment is to reduce pain, improve function and avoid unnecessary interventions. We combine protection, splint care, physiotherapy/hand therapy, analgesics and ergonomic adjustments - individually dosed and evaluated for a limited time.

Conservative therapy should be implemented consistently over several weeks (typically 6-12) and reviewed based on your goals. If pain and functional deficits remain severe, we discuss options for targeted infiltration or – if there is a clear indication – surgical procedures.

Injections and regenerative procedures: benefits and limitations

Intra-articular injections can temporarily relieve discomfort. The selection depends on the findings, previous illnesses and your preferences. There is no guaranteed long-term effect; we clarify opportunities and risks transparently.

• Corticosteroid injection: May reduce pain and reduce inflammation in the short term. Repetitions reserved, among other things because of possible tissue atrophy and risk of infection.
• Hyaluronic acid (viscosupplementation): Evidence for the wrist is limited; possible as an experiment in individual cases.
• PRP (platelet-rich plasma): Data on wrist osteoarthritis is inconsistent; may be considered for selected patients.
• Technology: If possible, image-controlled (ultrasound/fluoroscopy) for precise application and minimization of risks.

Important: Injections do not replace basic measures such as stress management, splints and hand therapy. We make decisions together based on the findings and your goals.

Splints, physiotherapy and ergonomics in detail

A coordinated combination of orthotic care and targeted hand therapy forms the backbone of conservative treatment.

• Orthosis: Short wrist splint stabilizes in everyday situations. The goal is measured relief, not immobilization over a long period of time.
• Therapy goals: Maintaining mobility, improving neuromuscular control, pain-adapted strengthening, training in everyday movement patterns.
• Exercises: Isometric forearm extensors/flexors, controlled active movements in the pain-free area, coordination exercises (e.g. with therapeutic clay/hand trainer).
• Ergonomics: workplace analysis, shock-absorbing gloves for vibration, avoiding extreme wrist angles, break management.

Surgical options: targeted and functionally gentle

Surgical measures can be considered if, despite consistent implementation, conservative strategies do not help sufficiently and everyday life remains significantly restricted. The choice of procedure depends on the location of the osteoarthritis, the stage (e.g. SLAC/SNAC pattern), age, professional/sporting requirements and ligament stability.

• Arthroscopy (debridement/synovectomy): Can reduce pain in the case of localized cartilage damage and inflammatory synovial fluid. Range of motion is usually maintained.
• Partial wrist denervation: severing selected pain-conducting nerve branches to reduce pain without changing the mechanics. Functional, individual effect.
• Scaphoidectomy with four-corner fusion (lunate, triquetrum, capitatum, hamatum): Best practice for SLAC/SNAC with midcarpal osteoarthritis; The goal is to reduce pain while maintaining a functional range of motion.
• Capitolunary fusion (selective partial arthrodesis): For osteoarthritis limited to the capitolunate surface; preserves more mobility than a complete arthrodesis.
• Proximal Row Carpectomy (PRC): Removal of the proximal carpal row; suitable if the articular surfaces between the head of the capitate and the radius are preserved. Maintains range of motion and strength to a level suitable for everyday use; not useful for every configuration.
• Total wrist arthrodesis: Ultima ratio for severe, treatment-resistant pain and global osteoarthritis; little pain, but no more movement in the wrist.

No method is “best” for everyone. We discuss realistic expectations: pain can often be reduced, mobility depends on the procedure and initial condition. Risks (e.g. infection, delayed bone healing, hardware irritation, persistent discomfort) are explained in advance.

Course and prognosis

Midcarpal osteoarthritis is usually a chronic, slowly progressive disease. With consistent conservative therapy, many of those affected achieve significant relief and better everyday function. If wear and tear is advanced, joint-preserving or stiffening procedures can often noticeably reduce pain; however, the range of motion remains reduced depending on the procedure.

• The aim is to gain functionality despite structural changes.
• The course varies depending on the cause (e.g. instability, collapse pattern) and occupational/sporting stress.
• Regular follow-up checks help to adjust therapy goals and detect overload at an early stage.

Everyday life, work and sport

Many activities are still possible with adjustments. The focus is on good self-management - knowing what is good, what is harmful, and how stress can be controlled.

• Favor neutral wrist positions; Avoid extreme dorsal bending.
• Choose low-impact sports (e.g. cycling with ergonomic handles, swimming with adapted technique); Support sports are often only possible to a limited extent.
• If necessary, use a supportive orthosis for stressful activities.
• Plan micro-breaks and alternate gripping types to reduce constant strain.
• After operations, the load is increased gradually according to individual instructions.

Prevention and self-help

• Early diagnosis and treatment of ligament injuries and fractures of the wrist.
• Targeted training of the forearm muscles, coordination and grip variability.
• Quitting smoking supports tissue healing.
• Ergonomic work equipment and shock-absorbing gloves in case of vibration.
• Increase stress slowly and pay attention to warning signals.

When should I seek medical advice?

• Acute pain with swelling/misalignment after an accident.
• Persistent pain at rest, pain at night, significantly increasing restriction of movement.
• Numbness/tingling in the fingers, loss of strength, or dropping objects.
• Redness, overheating, fever – suspected infection.
• New snapping/blocking phenomena.

These signs should be clarified promptly by a doctor in order to prevent complications and initiate the correct treatment.

Related clinical pictures (differential diagnoses)

Depending on the symptoms, other forms of osteoarthritis or circulatory disorders may be the cause. A clear distinction is important because treatment options and prognoses vary.

• Radiocarpal osteoarthritis (wear between the radius and the proximal carpal row).
• STT osteoarthritis (scaphoid-trapezium-trapezoid).
• Rhizarthrosis (saddle joint).
• Finger osteoarthritis (DIP, PIP, MCP).
• Kienböck's disease (lunate necrosis) and Preiser's disease (scaphoid necrosis).
• Nonunions after fractures, especially a. Scaphoid.