8.1 Fractures, Joint Replacements & Orthopedic Protocols
Key Takeaways
- Posterolateral total hip arthroplasty (THA) requires strict adherence to three cardinal precautions: no hip flexion beyond 90 degrees, no internal rotation, and no adduction past midline; anterolateral THA prohibits hip extension, external rotation, and adduction.
- Total knee arthroplasty (TKA) rehabilitation emphasizes early active range of motion and continuous full knee extension in bed, with a strict contraindication against placing pillows directly beneath the operative knee.
- Weight-bearing statuses dictate safe transfer and ADL techniques, ranging from Non-Weight-Bearing (0% load), Toe-Touch/Touch-Down Weight-Bearing (10–15% load for balance only), to Partial Weight-Bearing (20–50% load).
- Reverse Total Shoulder Arthroplasty (rTSA) alters glenohumeral biomechanics by using the deltoid as the primary elevator for rotator cuff-deficient shoulders, requiring sling immobilization and protocol-driven passive-to-active movement progression.
- The Bunnell-Littler test differentiates intrinsic muscle tightness from PIP joint capsular tightness following distal radius fractures: greater PIP flexion with the MCP flexed indicates intrinsic tightness, whereas equal limitation in both MCP positions confirms capsular restriction.
Fractures, Joint Replacements & Orthopedic Protocols
Orthopedic rehabilitation within occupational therapy integrates biomechanical and rehabilitative frames of reference to restore functional independence following joint arthroplasty, trauma, and skeletal fractures. Clinical mastery requires a rigorous understanding of surgical approaches, biomechanical precautions, weight-bearing restrictions, adaptive strategies for activities of daily living (ADLs), and differential assessment of soft tissue versus articular stiffness.
1. Total Hip Arthroplasty (THA) & Hip Fractures
Hip fractures and advanced osteoarthritis are primary indications for surgical intervention, including hemiarthroplasty, open reduction internal fixation (ORIF), and total hip arthroplasty (THA). The surgical approach dictates the structural stability of the prosthetic femoral head within the acetabular cup and establishes strict movement precautions to prevent postoperative dislocation.
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| TOTAL HIP ARTHROPLASTY (THA) SURGICAL APPROACHES |
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| Surgical Approach | Cardinal Movement Precautions | Functional / ADL Implications |
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| **Posterolateral** | 1. NO hip flexion > 90° | • Use reacher, sock aid, shoehorn |
| *(Most Common)* | 2. NO internal rotation | • Elevated toilet seat & shower chair|
| | 3. NO adduction past midline | • Abduction wedge pillow in bed |
| | (no crossing legs or ankles) | • Pivot on unaffected leg during turn|
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| **Anterolateral** | 1. NO hip extension | • Avoid stepping backward with leg |
| | 2. NO external rotation | • Avoid pivoting outward on leg |
| | 3. NO adduction past midline | • Abduction wedge in supine/sitting |
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| **Direct Anterior** | • Minimal standard precautions | • Early functional mobilization |
| | • Avoid extreme hyperextension and | • ADLs performed with normal biomech|
| | excessive external rotation | within client pain tolerance |
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Biomechanical Rationale & Adaptive ADL Integration
Following a posterolateral THA, the posterior capsule and external rotator musculature are incised and repaired. Flexing the hip past 90°, internally rotating, or adducting the operative lower extremity creates posterior displacement forces that risk pushing the femoral head out of the acetabulum.
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| POSTEROLATERAL THA: ADAPTIVE EQUIPMENT & ADL MATRIX |
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| ADL Domain | Compensatory Equipment & Biomechanical Technique |
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| **Lower Body** | • **Dressing Stick / Reacher:** Grasps waistband and lowers pants over |
| **Dressing** | operative foot first; undress non-operative foot first. |
| | • **Sock Aid:** Slides sock onto foot without exceeding 90° hip flexion. |
| | • **Long-Handled Shoehorn:** Donning footwear while maintaining trunk 90°.|
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| **Toileting &** | • **Elevated Toilet Seat / Commode:** Prevents hip flexion past 90°. |
| **Bathing** | • **Shower Chair & Long-Handled Sponge:** Wash lower extremities safely. |
| | • **Tub Transfer Bench:** Client slides across bench; avoids stepping. |
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| **Bed Mobility &** | • **Abduction Wedge Pillow:** Positioned between legs in supine and during|
| **Transfers** | log-rolling toward the non-operative side. |
| | • **Sit-to-Stand:** Slide operative leg forward in extension before stand.|
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2. Total Knee Arthroplasty (TKA)
Total Knee Arthroplasty (TKA) involves resurfacing the femoral condyles, tibial plateau, and patella with metal and polyethylene components. Unlike THA, TKA typically carries no hip-style dislocation precautions, but prioritizes early active range of motion, edema management, and joint contracture prevention.
Clinical Management and Postoperative Priorities
- Continuous Full Knee Extension: Maintaining full terminal knee extension (0°) is critical for normal gait mechanics. A severe clinical error is placing a pillow directly beneath the operative knee in bed. While this provides short-term comfort by placing the knee in slight flexion, it rapidly causes an intractable knee flexion contracture.
- Early Active/Active-Assisted ROM: Initiate active quadriceps sets, hamstring sets, ankle pumps, and heel slides within surgeon-approved limits. Continuous Passive Motion (CPM) devices may be prescribed to promote early passive flexion.
- Pain & Edema Control: Cryotherapy, elevation of the entire lower extremity with the knee straight (pillows beneath calf/ankle, not popliteal fossa), and compression stockings (TED hose).
- Functional Transfers and Mobility: Bed mobility, chair transfers using armrests while extending the operative leg forward, and car transfers (backing onto the seat and swinging both legs together).
3. Weight-Bearing Statuses
Orthopedic surgeons specify weight-bearing limitations based on bone quality, fracture stability, fixation hardware (screws, intramedullary rods, plates), or prosthetic fixation (cemented versus non-cemented/porous ingrowth).
| Weight-Bearing Classification | Prescribed Load (% Body Weight) | Clinical Definition & Biomechanical Instructions |
|---|---|---|
| Non-Weight-Bearing (NWB) | 0% | Operative extremity must not touch the ground or support any body weight during standing, transfers, or ambulation. Requires crutches or walker. |
| Toe-Touch / Touch-Down (TTWB / TDWB) | 10% – 15% | Only the toes of the operative extremity may touch the floor solely for balance control. Foot must not bear weight (the 'eggshell' analogy: do not break an egg underfoot). |
| Partial Weight-Bearing (PWB) | 20% – 50% | Operative extremity may support a designated percentage (typically up to 50%) of body weight. Measured using bathroom scale feedback. |
| Weight-Bearing as Tolerated (WBAT) | Variable (0%–100%) | Client determines load based on comfort, pain threshold, and stability. Ranges from partial to full weight bearing. |
| Full Weight-Bearing (FWB) | 100% | Client may bear 100% of body weight on the extremity without restrictions. Assistive devices used solely for balance if needed. |
4. Shoulder Arthroplasty & Rotator Cuff Pathology
Surgical reconstruction of the glenohumeral joint is categorized into conventional anatomical replacement and reverse replacement, each with distinct biomechanical principles.
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| TOTAL SHOULDER ARTHROPLASTY (TSA) vs. REVERSE TOTAL SHOULDER (rTSA) |
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| Parameter | Total Shoulder Arthroplasty (TSA) | Reverse Total Shoulder (rTSA) |
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| **Anatomical Configuration** | Glenoid cup + Humeral head ball | Glenosphere ball + Humeral cup|
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| **Primary Indication** | Intact, functional rotator cuff | Severe rotator cuff tear |
| | with severe glenohumeral OA | arthropathy / massive cuff tear|
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| **Primary Motor Driver** | Rotator cuff musculature | **Deltoid muscle** (increased|
| | (supraspinatus, infraspinatus) | lever arm / mechanical advantage)|
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| **Postoperative Precautions** | • No active internal rotation | • No shoulder hyperextension |
| | (protects subscapularis repair) | • No combined adduction and |
| | • No heavy lifting or pushing | internal rotation behind back|
| | • No weight-bearing through arm | • Sling worn 4–6 weeks |
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Phased Shoulder Rehabilitation Protocols
- Early Phase (Weeks 0–4): Sling immobilization worn 24/7 except for hygiene and prescribed exercises. Codman's pendulum exercises (passive gravity-assisted swinging of the arm while leaning forward, using trunk momentum rather than active shoulder musculature). Passive forward elevation in the scapular plane and gentle external rotation strictly within surgeon parameters. Active distal ROM (elbow, wrist, digits).
- Intermediate Phase (Weeks 4–8): Active-assisted to active ROM. Light isometric exercises avoiding resisted internal rotation if subscapularis was repaired.
- Strengthening Phase (Weeks 8–12+): Progressive resistive exercises (PREs), scapular stabilization, rotator cuff/deltoid strengthening, and gradual reintegration of functional bilateral ADLs.
5. Upper Extremity Fractures & Clinical Screening
Upper extremity fractures demand precise balance between anatomical immobilization for osseous union and early controlled mobilization to prevent capsular contracture, tendon adhesions, and complex regional pain syndrome (CRPS).
Humeral Shaft Fractures
- Mechanism & Management: Direct trauma or rotational force. Non-operative management utilizes a hanging arm cast initially, transitioning to a functional Sarmiento fracture brace (circumferential compression brace allowing full active elbow and shoulder movement while maintaining fracture alignment).
- Critical Neurological Complication: Radial Nerve Palsy occurs in up to 18% of mid-to-distal third humeral shaft fractures (spiral groove entrapment). Clinical signs include wrist drop, inability to actively extend MCP joints of digits and thumb, and sensory loss over the dorsal first web space. OT fabricates a dynamic wrist and MCP extension orthosis to maintain functional hand opening during nerve regeneration.
Distal Radius Fractures
Distal radius fractures are the most common upper extremity fractures, classified by displacement direction:
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| COLLES' FRACTURE vs. SMITH'S FRACTURE COMPARISON |
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| Feature | Colles' Fracture | Smith's Fracture |
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| **Mechanism of Injury**| Fall onto Outstretched Hand (FOOSH)| Fall onto dorsum of flexed wrist or |
| | with wrist in **extension** | direct blow to flexed wrist |
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| **Displacement** | Distal fragment displaced | Distal fragment displaced |
| | **dorsally** | **volarly / anteriorly** |
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| **Clinical Deformity**| **'Dinner Fork' Deformity** | **'Garden Spade' Deformity** |
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| **Complications** | Median nerve compression (acute | Median nerve compression, triangular |
| | carpal tunnel), EPL tendon rupture| fibrocartilage complex (TFCC) tears |
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Screening for Intrinsic Muscle vs. Joint Capsular Tightness: The Bunnell-Littler Test
Following distal radius immobilization, clients frequently exhibit digit stiffness. The therapist must determine whether limitation in proximal interphalangeal (PIP) joint flexion is caused by intrinsic muscle tightness (lumbricals and interossei) or true PIP capsular tightness.
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| BUNNELL-LITTLER TEST PROTOCOL |
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| STEP 1: Position MCP Joint in PASSIVE EXTENSION. |
| Attempt to passively flex the PIP joint. |
| |
| STEP 2: Position MCP Joint in PASSIVE FLEXION. |
| Attempt to passively flex the PIP joint. |
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| CLINICAL INTERPRETATION: |
| • Case A (Intrinsic Muscle Tightness): |
| PIP joint flexes MORE when MCP is flexed than when MCP is extended. |
| (Rationale: Flexing the MCP puts intrinsics on slack, allowing the PIP to flex). |
| |
| • Case B (PIP Joint Capsular Tightness): |
| PIP joint flexion remains EQUALLY LIMITED regardless of whether the MCP is flexed or extended. |
| (Rationale: The restriction is intrinsic to the PIP collateral ligaments/capsule itself). |
| |
| • Case C (Extrinsic Extensor Tendon Adhesions / Tightness): |
| PIP joint flexes MORE when MCP is extended than when MCP is flexed. |
| (Rationale: Flexing MCP increases tension on adhered extrinsic extensor digitorum communis). |
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An occupational therapist is providing ADL training to a 72-year-old client on postoperative day two following a right posterolateral total hip arthroplasty (THA). Which adaptive strategy and equipment configuration complies STRICTLY with the client's surgical precautions during lower-body dressing?
An occupational therapist evaluates a client 8 weeks after cast removal for a healed Colles' fracture of the right distal radius. The client demonstrates limited active and passive flexion of the right index finger PIP joint. When the therapist passively extends the MCP joint, the PIP joint flexes only 30 degrees. When the therapist passively flexes the MCP joint to 80 degrees, the PIP joint easily flexes to 95 degrees. What is the MOST ACCURATE clinical interpretation of this finding?
A 68-year-old client with a massive, irreparable rotator cuff tear and severe glenohumeral osteoarthritis undergoes a Reverse Total Shoulder Arthroplasty (rTSA). During initial occupational therapy intervention, what biomechanical principle MUST guide the therapist's treatment plan?