Consensus statement on prehabilitation and rehabilitation of osseointegration patients

Abstract

Rehabilitation protocols vary according to the osseointegration (OI) implant system and the institutions implanting bone-anchored limbs (BALs). While there are limited peer-reviewed OI publications quantifying details for optimizing surgical candidacy and rehabilitation protocols to ensure support across the BAL spectrum, the authors recommend a multidisciplinary team approach over the user's lifetime. Breakout sessions at the Global Collaborative Congress on OI (GCCO) were convened around key topics, including rehabilitation. Current best practice, gaps in the literature, and needs for future research were captured. The authors used these findings along with the available peer-reviewed literature and expert opinion to frame the consensus statements presented in this article. The authors present 3 consensus statements describing each phase of care—preoperative, perioperative, and postoperative.

1. Introduction

Rehabilitation protocols vary according to the osseointegration (OI) implant system and the institutions implanting bone-anchored limbs (BALs). A contemporary scoping review identifies that published peer-reviewed literature that describes or evaluates approaches to the presurgical, perisurgical, and postsurgical care for OI patients is limited and has few specific guidelines.¹ Aspects of rehabilitation involving physical therapy, prosthetic fitting, and optimal recovery need to be better understood and studied to optimize short-term and long-term patient outcomes. The goal of this consensus article, which is based on available publications and expert opinion by the authors, is to identify necessary phases of rehabilitation and integral disciplines and components in the process among the various types of OI implant systems. The various types are defined as screw/threaded fixation (OPRA), press-fit (OPL/ILP, OTN, AQ solutions, Signature), and hybrid (POP, Compress; Table 1).²

Table 1.

Implant type and manufacturer.

Type	Implant Name	Manufacturer	City/Country
Threaded fixation	OPRA	Integrum	Sweden
Press-fit	OPL/ILP	Osseointegrated prosthetic limb	Italy (Australian design)
Press-fit	OTNi	Osseointegration of the Netherlands	The Netherlands
Press-fit	AQ solutions	ReVivo solutions	Germany
Press-fit	Signature	Signature implants	Australia
Hybrid/press-fit	POP	DJO	Utah, United States
Cross-pin	Compress	Balmoral	United States

2. Methods to Develop Consensus

Breakout sessions at the Global Collaborative Congress on OI (GCCO) were convened around key topics, including rehabilitation. Physicians, researchers, therapists, prosthetists, and patient advocates participated in moderated discussions at the 2022 and 2023 GCCO meetings. Current best practice, gaps in the literature, and needs for future research were captured. The authors used these findings along with the available peer-reviewed literature and expert opinion to frame the consensus statements presented in this article.

The 3 phases of care—preoperative, perioperative, and postoperative—each have a different focus for the patient. Accordingly, the medical professionals supporting that patient should help with the immediate and later needs.³ Our recommendations are framed in the context of these periods to present a temporal map for prehabilitation and rehabilitation.

3. Osseointegration Rehabilitation Phases

3.1. Preoperative Phase

The preoperative phase in this context is defined as the time from patient candidacy consideration until the occurrence of surgery. Generally, a patient initiates OI consideration through discussions with a surgeon or physiatrist. However, there are circumstances where OI conversation roles are reversed, including unremitting pain and/or ongoing barriers to optimal socket fit. For assessment of whether OI is appropriate for that patient, the physiatrist is responsible for ensuring the prosthesis and rehabilitation steps in the process are optimized. Prosthetic socket fit and alignment can be optimized by working with an experienced certified prosthetist (CP) and is an important step before deeming that the patient has failed socket management.⁴ Optimizing prosthetic componentry, such as microprocessor knee, needs to be addressed before pursuing OI. A surgeon is relevant in this phase to determine whether and how an OI may be an option, given the patient's bone, muscle, joint mobility, and skin conditions.

Working with a physical therapist (PT) experienced with prosthetic gait training is also key to ensuring that the patient has obtained the best possible ambulation pattern and maximized socket use for preferred activities. Identifying patient activity goals that may be inconsistent with manufacturers' guidelines assists in the decision-making process. The importance of limiting high-impact activities (Fig. 1) that place repetitive strain or torque on the OI implant is an ongoing discussion with the patient. Future studies are needed to determine restrictions of and precautions for OI implants and recommended activity levels.

Figure 1.

Qualifying impact activity.

Furthermore, understanding that people with acquired limb loss often need time and support to develop coping skills to accept their amputation is required for optimizing mental health. This may involve health care professionals such as social workers, peer visitors, support groups, and psychologists/counselors, who specialize in limb loss and provide education and support. Psychosocial and medical barriers often require extended periods to allow for optimization. Social determinants of health must be discussed as diminished mobility adversely affects self-care, safety, transportation, employment, and caregiving. Medical optimization may require a multilayered approach including substance use treatment, pain management, endocrinology or weight management, cardiology, and psychology. OI may necessitate months of preparation, so establishing a comprehensive medical team approach is requisite to confirming candidacy and producing promising outcomes.

Physician responsibilities are as follows:

• Referral for substance abuse management if a concern is identified (opiate/pain, alcohol, tobacco)

• Referral for mental health management if a concern is identified (routine vs. individualized psychologist/psychiatrist)

• Referral for medical optimization and surgical clearance (diabetes, cardiac, rheumatologic, etc)

• Inclusion of concomitant surgery needs (nerve reconstruction,⁵ soft-tissue management⁶)

• A comprehensive team including orthopaedics, plastic surgery, physical medicine and rehabilitation (PM&R/physiatrist), PT, CP, social work, behavioral health, patient navigator, and insurance specialist

3.2. Physical Medicine and Rehabilitation

Amputation management for people with limb loss ideally occurs under the care of a PM&R physician, a physiatrist, who oversees the prosthetic and rehabilitation process after primary amputation. The physiatrist will often be the one who initially screens the amputee for appropriateness for OI based on the OI criteria (mentioned in an article in this supplement by Stoneback et al⁷ for a further discussion of patient selection; Fig. 2).

Figure 2.

OI criteria.

The best outcome for an amputee undergoing OI is with a well-informed candidate who has been optimized physically, prosthetically, and psychologically.⁸ Education regarding restrictions or other activities that would increase the risk of infection involving the transcutaneous connector may also be addressed by the physiatrist and the rehabilitation team.

3.3. Physical Therapy

Forming a partnership with a physical therapy team trained to manage patients with lower limb OI should start before surgery. Establishing a comprehensive baseline during a preoperative evaluation that considers cardiovascular response to exercise, strength and range deficits, physical abilities, home setup, and durable medical equipment needs assists with developing a plan of care to maximize postsurgical outcomes. Patients seeking OI typically have decreased activity and fitness levels because of limited use of a traditional socket prosthesis; therefore, a patient-centered home exercise program aiming to reduce soft-tissue contractures, prepare osseous structures through load bearing, strengthen limb/core musculature, and enhance cardiovascular fitness is essential to enhance recovery and improve quality of life following surgery.^8,9 Prospective candidates often have questions and concerns regarding return-to-function time frames and activity restrictions, so the PT works to set appropriate expectations and provide tailored education. In addition, the PT serves as an intermediary resource for connecting prospective OI patients to other team members and peer support. Peer-to-peer OI opportunities foster genuine discussions about the entire experience and support question/answer feedback on a patient level. Fig. 3 illustrates the significance of connecting all the pieces of preoperative therapy-related patient care; missing a piece contributes to vulnerability in outcome optimization (Fig. 3).

Figure 3.

The significance of connecting all the pieces of preoperative therapy–related patient care to avoid contributing to vulnerabilities in outcome optimization.

3.4. Orthopaedic and/or Plastic Surgeon

The determination of whether and how OI may be performed for a patient should be established by an orthopaedic and/or plastic surgeon during the preoperative phase. Some patients with a healthy, strong, painless, and suitably long residual femur or tibia may be relatively straightforward surgical candidates and mostly need other optimization procedures. Other patients, such as those with complex pain symptoms, damaged skin, recalcitrant joint contractures, neurologically compromised limbs, or limb segments with very short or other unusual anatomy, may need multiple surgical reconstructions before OI, or perhaps may be a very poor candidate. A surgical plan should be outlined and agreed to by the patient and surgeon(s) before embarking on a potentially highly involved preparatory journey, so that expectations are clear and realistic for all involved.

3.4.1. Consensus Statement

Preoperative phase: Medical and psychosocial patient optimization for OI warrants a comprehensive multidisciplinary approach over many months. Evaluation of the socket prosthesis and componentry to identify opportunities for improved fit will ensure that the patient has appropriate preoperative and postoperative prosthetic components. This requires presurgical planning.

4. Perioperative Phase

The perioperative phase starts at the day of surgery and continues at least through the immediate discharge from the operative episode and, depending on the postoperative protocol, likely should continue until the patient has recovered from acute dependency regarding self-care and mobility, which may be around the time the patient begins ambulatory physical therapy.

4.1. Surgery

The surgeon plays an important role in the perioperative phase to establish, reinforce, and evaluate infection prevention routines for the patient. This is detailed in the consensus article on infection and, most importantly, teaches the patient to adhere to proper hygiene care of the implant–skin portal.

4.2. Physical Medicine and Rehabilitation

Following surgery, PM&R should focus on working with the team/home prosthetist to ensure that the required prosthetic components, including the OI connector, are available and in good working condition in preparation to begin the rehabilitation protocol. Some practitioners advocate for appropriate torque and shock absorption in the device, but further studies are needed to establish this as a consensus recommendation.

Per protocols, perioperative therapy includes range-of-motion and non–weight-bearing exercises before being cleared by the surgeon to begin the next phase of weight bearing.

4.2.1. Consensus Statement

Perioperative phase: Implant-specific protocols determine progression through the rehabilitation process. Educating patients on activity level, mobility restrictions, and penetration site hygiene is crucial.

5. Postoperative Phase

For this article's purpose, the postoperative phase is considered to start around the time the patient is likely to resume a reasonable degree of autonomy and self-care, which may be as the patient starts early ambulation. Once the patient has been discharged from the hospital, the focus shifts to achieving independent ambulation. The current status of OI literature does not provide details regarding specific goals for advancing through potential phases of rehabilitation the way higher volume surgeries such as anterior cruciate ligament or joint replacement do, but the following principles guide the authors' perspectives.

5.1. Surgery

Following surgery, clearance for weight bearing and mobility will be provided by the surgeon. Although some implants have recommended protocols for patient loading after surgery, average loading protocol timings are displayed in Fig. 4.² Ultimately, the surgeon must agree with the loading progression and be aware of any potential issues the patient or other care team members express, especially pain or potential implant looseness. Intraoperative fractures, failure to achieve OI stability, and other complications can require modifications to the loading protocol. Radiographic imaging guides clearance for advancing through the protocol.

Figure 4.

Different time lines for each rehabilitation protocol that can affect when the physical therapist might begin in-clinic appointments with the patient.

5.2. Physical Medicine and Rehabilitation

Once OI surgery is complete, the patient with BAL should have ongoing follow-up with the comprehensive team. The focus of the physiatrist is to ensure coordination between the surgical, prosthetic, and rehabilitation team members. PM&R also works with the PT to ensure that the patient advances weight bearing according to the specific implant system's protocol. When the patient achieves the goal of ambulating without assistive devices, evaluating prosthetic componentry characteristics, such as torque and shock absorption, is warranted to maximize function, safety, and mobility. Continuity of care with long-term follow-up and management occurs under the PM&R specialty, which is crucial to maintaining and achieving best outcomes with the implant and prosthetic components including the maintenance of the OI/BAL connector. This often requires follow-up at various time points throughout the year and continuing throughout the amputee's life.

Having a working prosthesis available for starting the OI rehabilitation protocol is imperative. A bone-anchored prosthesis, which eliminates the socket, requires the addition of a connector that interfaces with the transcutaneous portion of the implant and the remainder of the prosthesis. At the end of 2023, CMS approved a new L-code for the OI connector and failsafe mechanism (L5991). The team surgeon or physiatrist is responsible for ordering the required prosthetic components including the OI connector by working with the CP to ensure that enough lead time is allowed for insurance authorization, approval, and delivery, requiring a coordinated process.

5.3. Physical Therapy

Initiation of physical therapy during the postoperative phase will vary from patient to patient. The type of implant helps to dictate a patient's plan of care; however, there are other limiting factors such as insurance authorization, locality to the hospital/rehabilitation facility, possible secondary procedures, and protocol restrictions.² The graphical illustration in Figure 4 highlights the different time lines for each rehabilitation protocol, which depicts when physical therapy starts with weight bearing using an osseointegrated full prosthesis (green).

6. Osseointegration Average Rehabilitation Protocol Time Lines

Fig. 4 demonstrates the overarching difference in rehabilitation time lines between implant types for transfemoral OI. Certain implants require a training prosthesis while others will transition patients to a full-length prosthesis, keeping the knee locked during initial weight bearing. If complications arise either intraoperatively or postoperatively, weight-bearing protocols will be delayed. Data were pulled from working protocols, some of which are not published at this time.^1,2,10

On initial evaluation, the PT should measure resting and activity vital signs, evaluate the tissue around the skin penetration site, address pain, measure range of motion (especially hip extension), test strength, and weigh the patient. Once baseline testing is complete, the therapist can begin exercises and activity interventions (Fig. 4) for the ipsilateral limb as per the protocol, unless the surgeon specifies delayed initiation related to impaired cortical bone remodeling or infection concerns. Strengthening of the contralateral limb, bilateral upper quarters, posterior chain, and core is launched regardless of the residual limb determinants.

Certain protocols require a short training prosthesis to begin weight bearing. Coordination with the prosthetist is needed to ensure that the training prosthesis is available when the patient is cleared to begin this phase of the rehabilitation protocol (yellow). The use of a scale is noted in certain protocols to determine safety when achieving percentage of body weight or increments in pounds as the patient begins partial weight bearing. A scale needs to be available for the patient to use at home with reinforcement of following the rehabilitation guidelines.

Loading the implant is imperative for bone ingrowth and should not be rushed.¹¹ By using changes in the numeric or visual pain scale as a guide and staying within the parameters of the rehab protocol, patients can gradually progress through weight bearing while reducing the risk of implant loosening. Over time, static and dynamic weight acceptance drills are incorporated into the plan of care, focusing on improving prosthetic trust by using newly developed osseoperception, defined as sensory function and proprioception.^2,12

When the patient is cleared to be fit with their full-length prosthesis, it is important to have the CP and PT present during this visit, if possible. This collaborative approach to prosthetic alignment can lead to improved gait patterns as the patient attempts their first steps. Proper loading of the prosthesis permits stance control and facilitation of knee flexion release. Using the patient's cell phone to capture mobility videos may be advantageous as OI rehabilitation can be lengthy and arduous. Serial digital videos can assist with quantifying physical gains, thereby improving personal well-being.

Owing to the frequency of patient visits, PT has a vital role in connecting patients to all modes of support, especially if a patient navigator has not been established. Communicating concerns with the surgeon regarding exudative changes, tissue concerns, or pain findings is essential. Capturing the details through pictures may generate a more specialized response and foster improved care particularly for those residing outside of the local catchment area. Arranging for the prosthetist to be onsite can yield more productive weight-bearing advancements and abilities when modifications need to be made to the prosthesis. To avoid delays in weight-bearing progression, there must be a concerted effort to orchestrate a solid team approach during the PT episode of care.

6.1. Consensus Statement

Postoperative phase: Successful BAL rehabilitation is often a lengthy and arduous process that demands commitment from a specialized team working to advance a motivated patient to achieve a desired quality of life. Uncompromised health status, personalized prosthetic componentry, physical abilities, high self-efficacy, and access to expert professional interventions optimize results.

7. OI Rehabilitation Research Gaps

Evaluating patient compliance with postoperative rehabilitation protocols (timing of weight bearing, progression, attendance of PT), regardless of the specific protocol used by the care team, will help establish the merits, shortcomings, or excesses of various protocols. No studies exist that describe the specific effectiveness or suitability of postoperative protocols. For example, PT protocols for anterior cruciate ligament and rotator cuff have many specific milestones to progress through phases of care, or sport-specific maneuvers to prepare for return to specific activities. This type of specific goal setting is lacking from the OI literature.

Furthermore, current protocols were modeled after the original screw/threaded OI implant with graduated progressive weight bearing. Interestingly, other orthopaedic devices that use press-fit applications, such as joint replacement, use immediate weight-bearing protocols. OI uses pain to assist with progression gradients in weight bearing, but total joint replacement models do not. In addition, some clinicians advocate for accelerated versus delayed or slower protocols; however, there are limited scientific data to drive these decisions. Further studies are needed to address these variabilities, including biomechanical bench research.

Patients living at a distance from the comprehensive team may have trouble with prolonged therapy protocols because of lack of access to experienced therapists and prosthetists. Secondarily, established protocols are limited, as mentioned above. Addressing access to care is a future direction for successful outcomes.

There is a lack of peer-reviewed literature regarding prosthetic componentry appropriate for OI. Furthermore, research is needed to determine which prosthetic device characteristics should be prescribed/recommended with BAL, highlighting a research gap in the prosthetic field.

8. Conclusion

While there are limited peer-reviewed OI publications quantifying details for optimizing surgical candidacy and rehabilitation protocols to ensure support across the BAL spectrum, the authors recommend a multidisciplinary team approach over the user's lifetime. The preoperative phase is a pivotal time frame for holistic health optimization under the leadership of the surgeon and physiatrist. Onboarding a robust team to address psychosocial, internal medicine, physical, and prosthetic needs is essential. The surgical team may require specialized members for neural integration, plastic surgery, and wound care. Postsurgically, the goal is recovery of mobility and ambulation, which requires the collaborative work of physiatry, physical therapy, and prosthetics. Across all disciplines, rehabilitation research will guide patient safety and meaningful outcomes.