(ii) Rehabilitation after hand fracture The principles of rehabilitation treatment for bone and joint injuries of the hand are the same as those for fractures in other parts of the body, i.e., accurate repositioning, effective immobilization and reasonable functional exercises. Wang Bo, Department of Rehabilitation, Songyuan Hospital of Traditional Chinese Medicine Rehabilitation treatment is generally divided into two phases: the period of immobilization after fracture reduction and the period of clinical healing of the fracture (i.e., the early and late stages). Fracture immobilization time varies depending on the site and degree of injury. Prolonged immobilization and persistent edema are the most important causes of joint stiffness. Therefore, early rehabilitation focuses on controlling edema and promoting smooth fracture healing. Frequent checking of the plaster splint for proper immobilization is needed to prevent plaster complications. Elevate the affected limb to reduce edema. For stable fractures, active activities can be started once swelling and pain are reduced (usually 5-7 days after injury). For unstable fractures and compound fracture dislocations, active movement exercises should be started after 3 weeks of immobilization. The purpose of rehabilitation in the later stage is completely different from the early stage, and its treatment focuses on: ① elimination of residual swelling; ② softening and loosening of fibrous scar tissue; ③ increasing the ROM of the joints; ④ restoration of normal muscle strength and endurance; ⑤ restoration of the functional coordination and dexterity of the hand. ⒈ Metacarpal fracture (1) thumb metacarpal base fracture Rehabilitation treatment points 1) Fixation period: the injured hand show, middle, ring, little finger passive and active movement. At the beginning of the passive-oriented, with the healthy hand to assist the injured hand for interphalangeal joint flexion and extension movements. After the local pain disappears, active movement is the main activity. 3 times a day, each activity time to localized mild fatigue is appropriate. 2）After fracture healing: ①Thumb abduction, adduction, palming and flexion/extension exercises. At the beginning of the passive-oriented, with the healthy hand holding the thumb, the movement should not be too large, to the fracture site pain limit, 3 times a day, 30min each time. ② one week later, the main active activities, the movement amplitude gradually increased. ③ Before doing joint active and passive movement, local wax therapy with wax bath or wax cake is better. (2) Other metacarpal base fracture: when the displacement of the fracture is obvious, give it a reset and immobilize it with plaster cast for 4 weeks. After that, active movement of fingers should be started gradually. (3) Metacarpal stem fracture: after the fracture is reset, the fingers are immobilized with plaster casts from the forearm to the proximal joints for 6 weeks, and the interphalangeal joints can be moved freely. (4) Metacarpal neck fracture 1) After fracture reduction, immobilize with plaster or splint for 3 weeks to 6 weeks, maintaining the wrist joint in 15° to 20° extension position, the metacarpophalangeal joint (MP joint) in 70° flexion, and the interphalangeal joint (IP) joint is usually not immobilized (if there is no problem of phalangeal rotation). (2) During the immobilization period, passive movement of the thumb and the healthy finger is the mainstay. active movement is allowed after 1 week, and passive movement of the distal interphalangeal (DIP) and proximal interphalangeal (PIP) joints of the injured finger is carried out for 3 to 5 days after the operation. Active and passive movements of the MP joints were prohibited to prevent the fracture end shear force from affecting fracture healing. Active movement of the wrist and elbow and shoulder joints. (3) 3 weeks to 6 weeks, remove the splint, the MP joint of the injured finger began to move, first passive additional movement to loosen the joint, followed by changing to assisted + active movement, when the range of motion of the MP joint was significantly improved, active resistance exercise training could be started. Eight weeks after the injury, muscle strength and endurance training was carried out. Complications of metacarpal fracture: mainly excessive dorsal edema, extensor tendon adhesion, joint capsule contracture, intrinsic muscle contracture. Peculiar phalangeal fracture ⑴ Proximal phalangeal fracture: after fracture revision, the metacarpophalangeal joint is flexed at 45°, the proximal interphalangeal joint is flexed at 90°, and it is immobilized with dorsal plaster strips for 4 weeks to 8 weeks. (2) Fracture of middle phalanx: after the fracture is restored, those who are angulated to the metacarpal side should be immobilized in flexion position; those who are angulated to the dorsal side should be immobilized in extension position for 4 weeks to 6 weeks. (3) Fracture of the terminal phalanx: after the correction, the proximal interphalangeal joint should be immobilized in flexion position of 90° and the distal interphalangeal joint should be immobilized in hyperextension position for 6 weeks with plaster or splint. Points of rehabilitation treatment for phalangeal fracture: 1) Fixation period: active movement of the healthy finger starts on the 2nd day after surgery. If there is no involvement between the healthy finger and the injured finger in flexion and extension activities, active movement is allowed; if there is involvement, passive activities are the main focus. Each activity should reach the maximum range. Carry out active movement of the wrist joint and forearm. When the pain and swelling of the injured finger begin to subside, passive flexion and extension of the injured finger can be done. The range of activities should be determined according to the fracture site and symptoms. If the middle and distal phalanges are fractured, the range of motion of MP joint can be larger; if the proximal phalanx is fractured, the MP joint motion will affect the fracture healing, so it is not suitable to move the MP joint. 2) After removal of external fixation: focus on interphalangeal joint flexion and extension exercises. If the fracture heals well, passive additional exercises are performed first. Following this, passive physiologic activities are the main focus, with active as a supplement. If the fracture is not firmly healed, the activities should be fixed with the healthy hand to protect the fracture site, and then, the passive activities of the interphalangeal joints. After the contracture and adhesion of the interphalangeal joints are loosened, active movement should be the main activity, supplemented by assisted movement, until the mobility of each joint is restored to the maximum range. Fractures of the distal interphalangeal joints are often associated with allergies at the finger tips and require desensitization, which can be achieved by rubbing the fingertips with substances of different textures, tapping and massaging the fingertips. (iii) Rehabilitation after tendon repair ⒈ hand tendon zoning At present, the common hand tendon zoning at home and abroad is the flexor tendon of the hand is divided into five zones (Figure 6-4-1), the tendon of the extensor tendon is divided into eight zones (Figure 6-4-2), and the tendon of the extensor digitorum superficialis is divided into six zones. Starting and ending points of each zone of the flexor tendon Tendon division Flexor tendon Finger Thumb Ⅰ distal interphalangeal joint proximal to tendon stopping point Thumb proximal middle of the joint to tendon stopping point Ⅱ sheath canal beginning to distal interphalangeal joint proximal sheath canal Ⅲ palm of the hand Department of the greater Fishbowl Ⅳ carpal tunnel area Carpal tunnel area Carpal tunnel area Ⅴ musculotendinous junction to proximal margin of the carpal tunnel Musculotendinous junction to proximal margin of the carpal tunnel Extensor tendon Starting and ending points of each zone Tendon division Finger Thumb Ⅰ distal interphalangeal Dorsal interphalangeal joint Ⅱ Middle interphalangeal joint Proximal interphalangeal joint Ⅲ Proximal interphalangeal joint Dorsal metacarpophalangeal joint Ⅳ Proximal metacarpophalangeal joint First metacarpophalangeal joint V Metacarpophalangeal joint Transverse carpal ligament Ⅵ Dorsum of the hand Carpal and forearm VII Dorsal transverse carpal ligament VIII Distal forearm Fig. 6=4-1 Flexor Tendon Zonation Figure 6-4-2 Extensor Tendon Zonation Flexor Tendon The hand functions based on the biomechanical equilibrium between extensors, flexors and intrinsic muscles. Hand function is based on the biomechanical balance of the extensor, flexor, and intrinsic muscles, and injury to any of these tendons can affect this balance. Traditionally, zone II flexor tendon injuries have been the most difficult to manage and are particularly susceptible to adhesion due to the fact that the superficial and deep tendons of the finger flexors are in the same tendon sheath. The theory behind flexor tendon repair is early mobilization, with special emphasis on the importance of early mobilization after zone II repair. (1) After surgery, the injured hand is immobilized with a dorsal plaster cast or a splint made of low-temperature thermoplastic material, maintaining 20° to 30° of wrist flexion and 45° to 60° of MP joint flexion; the interphalangeal joints are held in the straight position. One end of the rubber band is secured to the nail with glue, and its other end is secured to the dressing on the flexor side of the forearm with a pin after passing it through a carriage in the palm (Fig. 6-4-3). Figure 6-4-3 Early passive mobility device after flexor tendon repair (2) Early mobility is initiated 1 to 2 days after surgery, utilizing passive flexion of the interphalangeal joint with rubber band traction. Active extension of the interphalangeal joints is performed within the range of the splint. Active flexion of the interphalangeal joints and passive extension of the interphalangeal joints are prohibited during this period. To prevent flexion contracture of the PIP joint, the PIP joint should be maintained in full extension. The PIP should be immobilized with rubber bands between exercises and at night, and kept in an extended position in a splint. Passive flexion/extension of individual fingers is performed in a splint from the beginning of the procedure until 4 weeks. At week 4, active flexion of the injured finger is allowed. If the flexor tendon slides well (joint flexion ROM >75% of normal), this is indicative of mild postoperative scarring and splinting should be continued for 1.5 weeks. If the tendon slides little, this is indicative of severe postoperative scarring, and then the splint is removed and active movement exercises are performed. This includes exercises for individual fingers, superficial and deep tendons of finger flexion, hooking the fingers, making a fist, and so on. Finger flexion superficial and deep tendon sliding exercises ① Individual finger flexion superficial tendon exercises: maintain the MP joint in the straight position, fix the proximal end of the PIP joint, and ask the patient to actively flex the PIP joint, while maintaining the DIP joint in the straight position. ② Exercises for the deep flexor tendon: maintain the MP and PIP joints in the straight position, fix the proximal end of the DIP joint, and ask the patient to actively flex the DIP joint. ③ Hook fist exercise method: the PIP and DIP joints were flexed while the MP was straightened, thus ensuring the maximum range of motion of the superficial and deep tendons of finger flexion. ④ Right-angle fist exercise: the MP and PIP joints are flexed while keeping the DIP straight. This exercise, allows maximum range of sliding of the superficial finger flexor tendon. ⑤ Compound fist grip exercise: flexion of the MP, PIP, and DIP joints to maximize gliding of the superficial and deep flexor tendons. (3) Postoperative week 6, mild functional activities. If the PIP joint has a flexion contracture, a finger traction splint may be used. Postoperative week 7, resistance exercises, e.g., exercises with sponge balls and plastic therapeutic clay of varying strengths to maintain hand grip. Postoperative week 8, intensive resistance exercises to increase muscle strength and endurance. Postoperative week 12, active activities. 3) Rehabilitation after tendon release In order to achieve the desired goal of tendon release, firstly, the passive movement of the joint should be maximized as much as possible before the operation, and secondly, the tendon release should be complete and thorough during the operation. (1) Starting 24 hours after tendon release, the dressing is removed, and the patient exercises active flexion and extension. Exercises include: finger flexion of superficial and deep tendons sliding alone, hook finger, clenched fist, right-angle clenched fist and so on. (2) Active + assisted mobilization of MP, PIP and DIP joints for maximum range of flexion and extension. (3) Pain and edema are the most important causes of impediment to exercises and must be treated symptomatically. (4) At 2 weeks postoperatively, the stitches are removed. Soften and loosen the scar treatment. (5) If there is no tendon slippage after the release, functional electrical stimulation may be given 48 hours after surgery. (6) 2 to 3 weeks postoperatively: functional mobility exercises. (7) 6 weeks postoperatively, start resistance exercises. If the PIP joint contracture has been corrected after tendon release, a stretch splint may be used postoperatively to maintain the extension obtained during surgery. A few days after the release, practice several times a day with about 10 strokes each time and gradually increase the number and intensity of activities. Singed Rehabilitation after extensor tendon repair Traditionally, extensor tendon is treated with immobilization after surgery. Recent studies have proved that early flexion activities in a controlled range after extensor tendon repair (zones IV to VII) can help to reshape the scar tissue, allowing the tendon to have a greater degree of mobility, and also preventing adhesions. (1) Use a metacarpal splint after extensor tendon repair to immobilize the wrist joint in a 30° to 40° extended position while stretching and straightening all interphalangeal joints with rubber bands. An additional metacarpal splint was used to prevent flexion of the MP joint. The patient was instructed to actively flex the fingers within the range of the splint and to rely on elastic traction on the passive fingers. (2) One to three weeks postoperatively, practice active finger flexion and passive finger extension within the control of the splint. Passive finger flexion and extension were prohibited. 3 weeks later, ① remove the palmar splint and instruct the patient to continue active finger flexion and ② continue passive finger extension with elastic traction. 6 weeks later, remove the splint and begin active finger extension, including sliding exercises for each tendon. At 7 weeks postoperatively, resistance training was gradually started. (iv) Postoperative rehabilitation after peripheral nerve repair In recent years, it has been experimentally and clinically confirmed that after peripheral nerve dissection, the distal end of the injured nerve can secrete and release a mediator substance (diffusion factor), which attracts and guides the directional growth of proximally regenerated nerve fibers. The regeneration rate of nerve fibers is 1mm to 2mm per day, but because of the repair of severed nerve fibers, the nerve itself has to go through the process of Walle’s degeneration, the nerve suture end has a healing process, the regenerated nerve fibers have to go through the process of healing scar between the severed ends, and the regenerated nerve fibers have to grow and mature to reach the terminal structure. Therefore, the calculation from nerve repair to restoration of function can only be calculated at an average of 1mm per day. Purpose of rehabilitation: The main purpose is to teach the patient self-protection and compensatory ability. For example, if the skin is dry and the wound healing ability is reduced, the patient should be taught to clean the skin every day, how to take care of the skin, and how to maintain the softness and elasticity of the skin. Check the skin frequently for pressure pain and inflammation of overused skin. Excessive pulling or contracture of paralyzed or weak muscles should be avoided. During passive joint range of motion training, over-drawing should be prevented; protective splints should be chosen to prevent postural contractures, etc. The content of rehabilitation therapy varies at different stages, as shown in (Figure 6-4-4). 0 3 weeks 6 weeks 3 months 6 months 1 year Protection after repair Prevention of secondary deformities Increase in range of motion Enhancement of muscle strength Sensory retraining