Pinch

The most commonly performed surgeries for reconstructive pinch are:

  • Key-Pinch Grip – Brachioradialis to Extensor Carpi Radialis Longus, Flexor Pollicis Longus split tenodesis. The IP joint of the thumb may need to be stabilized to prevent excessive IP flexion.
  • Key-Pinch Grip with or without Hook Grip – Brachioradialis to Flexor Pollicis Longus with or without Flexor Digitorum Profundus tenodesis or Brachioradialis to Extensor Carpi Radialis Longus.
  • Key-Pinch Grip and Hook Grip – Brachioradialis or Pronator Teres to Flexor Pollicis Longus and Brachioradialist or Extensor Carpi Radialis Longus to Flexor Digitorum Profundus

Additional procedures to increase thumb pinch and thumb opposition may also be completed.

Author Year

Country

Research Design

Score

Total Sample Size

Methods Outcome
Wangdell et al., 2018

Sweden

Cohort

N=37

Population: Experiencing pain (n=17): Mean age=43.6±13.4 yr; Gender: males=13, females=4; Time since injury: 6.1±9.5 yr; Level of injury: C5 – C7; Severity of injury: not reported.

Not experiencing pain (n=20): Mean age=42.4±13.8 yr; Gender: males=11, females=9; Time since injury: 6.2±8.4 yr; Level of injury: C5 – C7; Severity of injury: not reported.

Intervention: Participants with (n=17) and without (n=20) preoperative neuropathic pain in the arm/hand were evaluated for outcome measures pre and post surgical grip reconstruction.

Outcome Measures: Grip strength; Grasp ability; Prioritized activity outcome.

1.     There were no significant differences between the pain and no pain groups regarding grip strength, grip ability or activity performance and satisfaction (p>0.05).

2.     Both groups experienced improvements in all aspects of the prioritized activity outcome and there were no differences in the ability to fulfill postoperative treatment (p>0.05).

McCarthy et al., 1997

USA

Pre-Post

N=135

Population: Age: 8-58 yr; Gender: males=103, females=30; Level of injury: tetraplegia; Follow-up time: 3-24 mo.

Intervention: Extrinsic hand reconstruction with intrinsic balancing procedures versus extrinsic reconstructions without intrinsic balancing procedures.

Outcome Measures: Pre-and post-operative assessments of grip strength (on the second position of the Jamar dynamometer), Activities of Daily Living (ADL).

1.     All patients had preoperative grip strength of zero. At an average follow-up period of 31 mo, the average final grip strength was 69N (7kg) and the ADL improvement score averaged 35.5.

2.     Patients who underwent an intrinsic procedure had a statistically stronger grip (72N) than patients who did not undergo an intrinsic procedure (p=0.026).

3.     Ocular group: Five patients with an intrinsic procedure had a statistically stronger grip than patients without an intrinsic procedure (p=0.028).

4.     With the exception of Ocular group 7, in which eight patients did not undergo an intrinsic procedure due to their ability to balance tension between the extensors and flexors, all other Ocular groups with an intrinsic reconstruction showed stronger grip than patients without an intrinsic reconstruction.

5.     ADL improvements scores were higher but not statistically significant for those with intrinsic rebalancing versus those without rebalancing.

6.     There was significant difference between the hands treated by FDS lasso and those treated by intrinsic tenodesis when patients were stratified by Ocular level.

7.     There was also no significant difference in grip strength results between the FDS lasso versus the intrinsic tenodesis procedures when stratified by both Ocular level and type of extrinsic reconstruction, both surgical techniques were effective in improving strength and ADL.

House et al., 1992

USA

Case Series

N=18

Population: Age: 16-29 yr; Gender: males=14, females=4; Level of injury: C5-C6; Time since injury: 16 mo-13 yr; Mean follow-up time: 3.5 yr.

Intervention: Carpal-metacarpal fusion was performed; along with extensor pollicis longus tenodesis and motor transfer to flexor pollicis longus.

Outcome measures: Function of the hand, subjective pain scale, Level of satisfaction with surgery and rehabilitation, Activities of Daily Living (ADL).

1.     All patients reported a significant increase in independent hand function in relation to ADLs, no patient reported hand function was worse after surgery.

2.     Technique provided a reliable and reproducible key pinch.

3.     All patients had significant improvement in functional ADLs and highly satisfied with results of surgery.

Waters et al., 1985

USA

Case Series

N=15

Population: Age: 20-47 yr; Gender: males=13, females=2; Time since injury: 8 mo-18 yr; Follow-up time: 8-48 mo.

Intervention: Surgery.

Outcome Measures: Pinch strength, Activities of Daily Living (ADL) reports, Brachioradialis (BR), Flexor Pollicis Longus (FPL), Flexor Digitorum Profundus (FDP), Extensor Capri Radialis Longus (ECRL), Extensor Pollicis Brevis (EPB).

1.     Release of the BR and suture to the FPL. In 16/17 hands, fixation of the IP joint of the thumb was obtained with a Moberg screw. 11/17 patients lacked active thumb extension had tenodesis of the thumb extensors to the MCP to prevent excessive flexion of the MCP joint.

2.     FPL and EPB were secured to the dorsum of the MC. 6/11 patients did not require tenodesis had sufficient strength in the FPL to extend the thumb.

3.     Two of six EIP was transferred to FPL for active extension.

4.     Satisfactory finger flexion present in 10 hands. In seven hands: intertendinous suture of all FDP tendons in four patients who had active flexion in the ulnar profundi of small and ring finger, but could not flex index finger.

5.     Transfer of PT to all FDP tendons in two patients; transfer of ECRL to all FDP tendons in one patient; transfer of FCU to all FDP tendons in one patient.

6.     Preoperative lateral pinch ranged from 0-0.15 lbs, post-operative lateral pinch ranged from 2.2-4 (depending on elbow and wrist position).

7.     Residual motor function in triceps (fair plus) (11 patients) and pinch strength; lateral pinch 5.1 lbs, strength fair or less (6patients) 2.0 lbs pinch.

8.     87% (13/15) reported significant improvement; four patients wanted stronger pinch.

9.     80% (12/15) could name four ADL activities that they were able to perform.

10.   13% (2/15) were dissatisfied.

11.   20% (3/15) reported discomfort tip of thumb.

Conclusion

There is level 4 evidence (from two case series studies: House et al. 1992Waters et al. 1985) that metacarpal fusion can increase pinch strength as well as improve the over all ability to complete daily living tasks.

There is level 4 evidence (from one pre-post study: McCarthy et al. 1997) that the addition of intrinsic balancing procedures to extrinsic hand reconstruction can improve pinch strength and the ability to perform daily living tasks compared to extrinsic hand reconstruction alone.