Surface Replacement Arthroplasty of the Proximal Interphalangeal Finger Joint
 
The proximal interphalangeal PIP joint (second joint from the fingertip) is prone to osteoarthritis. Osteoarthritis is a degenerative joint disease in which the smooth cartilage that covers the bone joint surfaces is either worn or becomes damaged over time. Symptoms include pain, weakness, deformity and stiffness. Many patients respond to non-operative treatment including activity modification, splinting and medication. In some cases, patients may require surgical management including arthroplasty. Arthroplasty (reconstruction or replacement) of the PIP finger joint is a procedure used for pain relief and restoration of functional motion in patients who retain good bone density, minimal ligament deformity, and preserved flexor and extensor function.

Joint replacement is commonly performed in the PIP joint as alternatives such as joint fusion can hinder power grasp and function of the hand. The small and ring fingers are good candidates for joint replacement as they are mostly used for gross hand movements such as grasping. The index finger is a less suitable candidate for a PIP joint replacement, as it is used in more fine motortasks such a pinch and key grip, and therefore must withstand the additional sideways forces placed on the joint. These forces cause excess stress on the joint implant and can lead to early implant breakage.

 

During surgery the arthritic joint ends of the affected finger are removed and replaced with a prosthetic or false joint. The replacement joint may be made of either pyrocarbon or silastic (silicone) material. The replacement joint allows for some range of movement, although this may be limited as its primary purpose is pain relief.

The pyrocarbon PIP joint replacement consists of 2 component parts and is made of an inert biocompatible material. The implant is anatomically designed to promote implant alignment and stability.

PyroCarbon Implants are designed to replicate anatomical joint surfaces, preserve bone and minimise disruption to the collateral ligament origins and insertions. The implant closely mimics that of a normal joint when the soft tissues are well preserved. PyroCarbon Implants are designed to withstand the demands of everyday hand functions and can provide pain relief and restore range of movement in the joint.

PYROCARBON PIPJ REPLACEMENT (DORSAL APPROACH):


-Taking care to preserve the dorsal veins, a longitudinal incision is made over the proximal interphalangeal joint.  The incision is deepened through the skin and subcutaneous tissues to expose the extensor mechanism.

-The extensor mechanism including the central slip is incised longitudinally and retracted to expose the joint.

-The dorsal part of the collateral ligaments are released and the joint flexed to expose the articular surfaces.

-The intramedullary cavity of the proximal phalanx is opened with an awl at the junction between the dorsal and middle third of the joint surface.

-An alignment guide is placed into the medullary canal and a bone saw is used to make a transverse cut across the distal part of the proximal phalanx, protecting the collateral ligaments during the procedure.

-The alignment guide is removed and the cut completed.

- Broaches of increasing size are used to creat the space for the stem of the implant in the medullary canal.

-The obliques osteotomy guide is used to make a second oblique cut to remove the articular condyles of the proximal phalanx.

-A transverse cut is then made across the base of the middle phalanx.

-The intramedullary canal of the middle phalanx is opened with an awl and then broaches.

-A burr and rongeurs are used to remove osteophytes and sharp edges that could damage the implant, and the canal is irrigated with saline to remove any debris.

-Trial implants of the proximal and then distal components are used to test for the correct implant size, range of motion, alignment and stability, before the definitive implants are inserted.

-The extensor mechanism is sutured, then the skin is sutured.

The PIP silastic finger joint replacement is designed to restore hand function, eliminate pain and improve cosmetic appearance in lower demand patients. The silastic joint replacement accommodates the unique anatomy and biomechanics of the PIP joint allowing maintenance of the flexion and extension of the joint without volar impingement.
SILICONE PIPJ REPLACEMENT (DORSAL APPROACH)

-Taking care to preserve the dorsal veins, a longitudinal incision is made over the proximal interphalangeal joint.  The incision is deepened throughout the skin and subcutaneous tissues to expose the extensor mechanism.

-The extension mechanism, including the central slip is incised longitudinally and retracted to expose the joint.

-The dorsal part of the collateral ligaments are released and the joint flexed to expose the articular surfaces.

-A bone saw is used to make a transverse cut across the distal part of the proximal phalanx, protecting the collateral ligaments during the procedure.

-It may be necessary to make a transverse cut across the base of the middle phalanx to remove this.  If removal of the base of the middle phalanx is not required, simply remove any osteophytes to form a good surface for the implant to  hinge against.

-The medullary canal of the proximal phalanx, and then the middle phalanx is opened with an awl at the junction of the dorsal and middle third of the joint surface.

-Broaches of increasing sizes are used to creat the space for the stem of the implant in the medullary canal, along its axis.

-A burr and rongeurs are used to remove osteophytes and sharp edges that could damage the implant, and the canal is irrigated with saline to remove any debris.

-Trail implants are used to test for the correct implant size, range of motion, alignment and stability, before the definitive implant is inserted.

-The extensor mechanism is sutured, then the skin is sutured.

 
Bones of the Hand (3d Interactive Model)

Animation demonstrating PIP joint replacement surgery 

Video footage of PIP arthroplasty surgery carried out by Dr Mike Hayton 

Silicone PIP Finger Joint replacement,

© Mike Hayton, Consultant Orthopaedic Surgeon,

Web link: http://www.mikehayton.com/

 

Website produced in collaboration with the University of Dundee and  NHS Tayside under the supervision of Miss Kirsty Munro, Consultant Plastic Surgeon, Ninewells Hospital, Dundee, DD1 9SY

  • LinkedIn Social Icon
  • Black Instagram Icon

 © 2019 Parsonsarts