Concentric and eccentric shoulder rehabilitation biomechanics.

The use of an impulse-momentum (IM) exercise technique was investigated for end-stage shoulder rehabilitation. The objectives of this study were to: (a) quantify the net shoulder joint forces and moments while using an IM system and (b) test the influence of gender and muscle loading type (concentric or eccentric) on kinetic and kinematic parameters. Fourteen healthy adults (eight males, six females) performed a repeated measures experiment on an instrumented device utilizing a cabled shuttle system. While maintaining 90 degrees of shoulder abduction and 90 degrees of elbow flexion, the subjects externally rotated their upper arm from 0 degrees to 90 degrees (concentric acceleration) and then internally rotated their upper arm back from 90 degrees to the 0 degrees position (eccentric deceleration). Shoulder joint forces and moments as well as rotational work and power were calculated using inverse dynamics (free-body forces and moments calculated at intersegmental joint centres). Overall concentric peak forces and moments were greater than eccentric peak forces and moments (P < 0.0001). Joint forces and moments reached a maximum during the initial phase of concentric loading (0 degrees to 45 degrees) compared with any other rotational position in the loading cycle (concentric 45 degrees to 90 degrees or eccentric 90 degrees to 0 degrees). The results also indicate that males experienced higher (P < 0.0001) average resultant peak joint forces (concentric 0 degrees to 45 degrees = 108.0 N and eccentric 90 degrees to 45 degrees = 87.2 N) than females (concentric 0 degrees to 45 degrees = 74.7 N and eccentric 45 degrees to 0 degrees = 56.0 N). In addition, males experienced higher (P < 0.0001) average resultant peak joint moments (concentric 0 degrees to 45 degrees = 30.4 N m and eccentric 45 degrees to 0 degrees = 21.0 N m) than females (concentric 0 degrees to 45 degrees = 19.7 N m and eccentric 45 degrees to 0 degrees = 12.8 N m).

Aquatic-based rehabilitation and training for the shoulder.

OBJECTIVE: To describe the application of aquatic rehabilitative exercise to injuries of the upper extremity. BACKGROUND: Water has been used for centuries as a medium for rehabilitation, relaxation, and training. Athletes use the pool to rehabilitate specific injuries, as a training medium during injury recovery, and as an alternative training site. The pool can be used to rehabilitate a number of upper extremity impairments, as well as to restore functional movement patterns in a resistive medium. DESCRIPTION: Exercises can be modified to be performed in pools of varying size and depth. Well-chosen equipment will enhance the rehabilitative opportunities for the clinician and patient. CLINICAL ADVANTAGES: All aspects of the rehabilitation program, including passive stretching, resistive exercise, functional movement patterns, and cardiovascular training, can take place in the same location. The water's warmth and buoyancy enhance stretching, while the buoyancy allows initiation of resistive exercise at a low level. The water's viscosity provides resistance throughout a movement pattern in any plane.

Nonoperative treatment for patellofemoral pain.

Patellofemoral pain, often called patellofemoral stress syndrome or patellofemoral joint dysfunction, is a commonly seen knee pain syndrome in patients of all ages. It is often a frustrating problem for both the patient and the clinician, as the source of pain can be elusive, making treatment choices difficult. Strategies have been proposed based upon potential sources of pain, including both operative techniques as well as conservative management. Current nonoperative treatment strategies and techniques in the treatment of patellofemoral pain are reviewed. Recommendations and criteria for progression of rehabilitation and suggestions for future research regarding patellofemoral pain are suggested.

Aquatic-based rehabilitation and training for the elite athlete.

Elite athletes are competing for longer seasons, training more hours, and taking less time off. This schedule may predispose the elite athlete to overuse injuries. When an injury occurs, aquatic-based rehabilitation may expedite the recovery process, as effective cardiovascular and musculoskeletal training may be accomplished by aquatic exercise. The pool may be used both during rehabilitation and postrecovery as an adjunctive tool. Knowledge of the unique physical properties of water, as well as the physiological responses to immersion both at rest and during exercise, will aid the physical therapist when designing a rehabilitation or training program for the athlete. Understanding the principles of movement in water will provide a foundation for creative use of water's unique properties.