Sling Duration After Left Shoulder Hemiarthroplasty
Patients should remain in a sling for 4 weeks after left shoulder hemiarthroplasty before beginning active physiotherapy.
Evidence-Based Recommendation
The standard immobilization period is 4 weeks based on the best available evidence for hemiarthroplasty rehabilitation 1. This duration balances two critical competing risks:
- Too early mobilization: Risks non-union of the greater tuberosity (particularly in fracture cases)
- Too late mobilization: Risks excessive shoulder stiffness and poor functional outcomes
The Supporting Evidence
A prospective study of 40 patients who underwent hemiarthroplasty for proximal humerus fractures used a conservative 4-week immobilization protocol before commencing physiotherapy 1. This approach achieved:
- 87.2% tuberosity union rate (though union was less reliable in patients over 70)
- Average elevation >130 degrees in those with healed tuberosities
- 51.3% excellent results, 33.3% satisfactory results
- No excessive stiffness despite the delayed mobilization
A 2020 UK survey of NHS rehabilitation protocols confirmed this practice pattern, finding a median sling duration of 4 weeks (range 0-8 weeks) across 43 patient information sheets from 40 NHS Trusts 2. Most protocols commenced passive exercise immediately but delayed active exercise until 4 weeks.
Practical Implementation Algorithm
Week 0-4 (Immobilization Phase):
- Continuous sling use except for hygiene
- Passive pendulum exercises may begin immediately (per surgeon preference)
- Important caveat: Remove the sling periodically when resting to reduce pain—one study showed immediate pain reduction of 1.35 points on a 10-point scale when the sling was removed 3
Week 4-6 (Active Motion Phase):
- Discontinue sling
- Begin active-assisted and active range of motion exercises
- Progress to functional activities
Week 5+ (Strengthening Phase):
- Initiate resisted exercises (median 5 weeks per UK data) 2
Week 6-12 (Return to Function):
- Return to driving at 6 weeks
- Return to general work at 12 weeks 2
Critical Pitfalls to Avoid
Age matters significantly: In the study using 4-week immobilization, patients over 70 (mean age 78.8) had only a 12.8% tuberosity non-union rate, but this was concentrated in the elderly population 1. Younger patients (<70 years) achieved excellent functional results with this protocol.
Patient challenges during immobilization: Be prepared to counsel patients that 84.5% will have difficulty sleeping for an average of 6.5 weeks, and most will need assistance with bathing, drying, and dressing for the first 2 weeks 4. Setting these expectations preoperatively improves satisfaction.
The sling paradox: While traditionally applied "for comfort," slings actually increase immediate postoperative pain 3. Instruct patients to remove the sling when resting in a supported position to reduce discomfort, while maintaining protection during ambulation and sleep.